path: root/doc/rfc/rfc5707.txt

Independent Submission                                         A. Saleem
Request for Comments: 5707                                        Y. Xin
Category: Informational                                          RadiSys
ISSN: 2070-1721                                              G. Sharratt
                                                              Consultant
                                                           February 2010


                  Media Server Markup Language (MSML)

Abstract

   The Media Server Markup Language (MSML) is used to control and invoke
   many different types of services on IP media servers.  The MSML
   control interface was initially driven by RadiSys with subsequent
   significant contributions from Intel, Dialogic, and others in the
   industry.  Clients can use it to define how multimedia sessions
   interact on a media server and to apply services to individuals or
   groups of users.  MSML can be used, for example, to control media
   server conferencing features such as video layout and audio mixing,
   create sidebar conferences or personal mixes, and set the properties
   of media streams.  As well, clients can use MSML to define media
   processing dialogs, which may be used as parts of application
   interactions with users or conferences.  Transformation of media
   streams to and from users or conferences as well as interactive voice
   response (IVR) dialogs are examples of such interactions, which are
   specified using MSML.  MSML clients may also invoke dialogs with
   individual users or with groups of conference participants using
   VoiceXML.

Status of This Memo

   This document is not an Internet Standards Track specification; it is
   published for informational purposes.

   This is a contribution to the RFC Series, independently of any other
   RFC stream.  The RFC Editor has chosen to publish this document at
   its discretion and makes no statement about its value for
   implementation or deployment.  Documents approved for publication by
   the RFC Editor are not a candidate for any level of Internet
   Standard; see Section 2 of RFC 5741.

   Information about the current status of this document, any errata,
   and how to provide feedback on it may be obtained at
   http://www.rfc-editor.org/info/rfc5707.






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IESG Note

   This RFC is not a candidate for any level of Internet Standard.  The
   IETF disclaims any knowledge of the fitness of this RFC for any
   purpose and in particular notes that the decision to publish is not
   based on IETF review for such things as security, congestion control,
   or inappropriate interaction with deployed protocols.  The RFC Editor
   has chosen to publish this document at its discretion.  Readers of
   this document should exercise caution in evaluating its value for
   implementation and deployment.  See RFC 3932 for more information.

Copyright Notice

   Copyright (c) 2010 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.

Table of Contents

   1. Introduction ....................................................4
   2. Glossary ........................................................5
   3. MSML SIP Usage ..................................................6
      3.1. SIP INFO ...................................................7
      3.2. SIP Control Framework ......................................8
   4. Language Structure .............................................15
      4.1. Package Scheme ............................................15
      4.2. Profile Scheme ............................................18
   5. Execution Flow .................................................19
   6. Media Server Object Model ......................................21
      6.1. Objects ...................................................21
      6.2. Identifiers ...............................................23
   7. MSML Core Package ..............................................26
      7.1. <msml> ....................................................26
      7.2. <send> ....................................................26
      7.3. <result> ..................................................27
      7.4. <event> ...................................................27
   8. MSML Conference Core Package ...................................28
      8.1. Conferences ...............................................28
      8.2. Media Streams .............................................29
      8.3. <createconference> ........................................31
      8.4. <modifyconference> ........................................33
      8.5. <destroyconference> .......................................34



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      8.6. <audiomix> ................................................35
      8.7. <videolayout> .............................................36
      8.8. <join> ....................................................43
      8.9. <modifystream> ............................................45
      8.10. <unjoin> .................................................46
      8.11. <monitor> ................................................47
      8.12. <stream> .................................................47
   9. MSML Dialog Packages ...........................................51
      9.1. Overview ..................................................51
      9.2. Primitives ................................................53
      9.3. Events ....................................................55
      9.4. MSML Dialog Usage with SIP ................................56
      9.5. MSML Dialog Structure and Modularity ......................57
      9.6. MSML Dialog Core Package ..................................58
      9.7. MSML Dialog Base Package ..................................63
      9.8. MSML Dialog Group Package .................................81
      9.9. MSML Dialog Transform Package .............................85
      9.10. MSML Dialog Speech Package ...............................88
      9.11. MSML Dialog Fax Detection Package ........................92
      9.12. MSML Dialog Fax Send/Receive Package .....................93
   10. MSML Audit Package ...........................................100
      10.1. MSML Audit Core Package .................................100
      10.2. MSML Audit Conference Package ...........................102
      10.3. MSML Audit Connection Package ...........................106
      10.4. MSML Audit Dialog Package ...............................108
      10.5. MSML Audit Stream Package ...............................110
   11. Response Codes ...............................................111
   12. MSML Conference Examples .....................................113
      12.1. Establishing a Dial-In Conference .......................113
      12.2. Example of a Sidebar Audio Conference ...................117
      12.3. Example of Removing a Conference ........................118
      12.4. Example of Modifying Video Layout .......................118
   13. MSML Dialog Examples .........................................120
      13.1. Announcement ............................................120
      13.2. Voice Mail Retrieval ....................................120
      13.3. Play and Record .........................................122
      13.4. Speech Recognition ......................................125
      13.5. Play and Collect ........................................125
      13.6. User Controlled Gain ....................................128
   14. MSML Audit Examples ..........................................128
      14.1. Audit All Conferences ...................................128
      14.2. Audit Conference Dialogs ................................129
      14.3. Audit Conference Streams ................................130
      14.4. Audit All Connections ...................................131
      14.5. Audit Connection Dialogs ................................131
      14.6. Audit Connection Streams ................................132
      14.7. Audit Connection with Selective States ..................133
   15. Future Work ..................................................134



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   16. XML Schema ...................................................134
      16.1. MSML Core ...............................................136
      16.2. MSML Conference Core Package ............................140
      16.3. MSML Dialog Packages ....................................148
      16.4. MSML Audit Packages .....................................170
   17. Security Considerations ......................................176
   18. IANA Considerations ..........................................176
      18.1. IANA Registrations for 'application' MIME Media Type ....176
      18.2. IANA Registrations for 'text' MIME Media Type ...........178
      18.3. URN Sub-Namespace Registration ..........................179
      18.4. XML Schema Registration .................................180
   19. References ...................................................181
      19.1. Normative References ....................................181
      19.2. Informative References ..................................182
   Acknowledgments ..................................................183

1.  Introduction

   Media servers contain dynamic pools of media resources.  Control
   agents and other users of media servers (called media server clients)
   can define and create many different services based on how they
   configure and use those resources.  Often, that configuration and the
   ways in which those resources interact will be changed dynamically
   over the course of a call, to reflect changes in the way that an
   application interacts with a user.

   For example, a call may undergo an initial IVR dialog before being
   placed into a conference.  Calls may be moved from a main conference
   to a sidebar conference and then back again.  Individual calls may be
   directly bridged to create small n-way calls or simple sidebars.
   None of these change the SIP [n1] dialog or RTP [i3] session.  Yet
   these do affect the media flow and processing internal to the media
   server.

   The Media Server Markup Language (MSML) is an XML [n2] language used
   to control the flow of media streams and services applied to media
   streams within a media server.  It is used to invoke many different
   types of services on individual sessions, groups of sessions, and
   conferences.  MSML allows the creation of conferences, bridging
   different sessions together, and bridging sessions into conferences.

   MSML may also be used to create user interaction dialogs and allows
   the application of media transforms to media streams.  Media
   interaction dialogs created using MSML allow construction of IVR
   dialog sessions to individual users as well as to groups of users
   participating in a conference.  Dialogs may also be specified using
   other languages, VoiceXML [n5], which support complete single-party
   application logic to be executed on the media server.



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   MSML is a transport independent language, such that it does not rely
   on underlying transport mechanisms and language semantics are
   independent of transport.  However, SIP is a typical and commonly
   used transport mechanism for MSML, invoked using the SIP URI scheme.
   This specification defines using MSML dialogs using SIP as the
   transport mechanism.

   A network connection may be established with the media server using
   SIP.  Media received and transmitted on that connection will flow
   through different media resources on the media server depending on
   the requested service.  Basic Network Media Services with SIP [n7]
   defines conventions for associating a basic service with a SIP
   Request-URI.  MSML allows services to be dynamically applied and
   changed by a control agent during the lifetime of the SIP dialog.

   MSML has been designed to address the control and manipulation of
   media processing operations (e.g., announcement, IVR, play and
   record, automatic speech recognition (ASR), text to speech (TTS),
   fax, video), as well as control and relationships of media streams
   (e.g., simple and advanced conferencing).  It provides a general-
   purpose media server control architecture.  MSML can additionally be
   used to invoke other more complex IVR languages such as VoiceXML.

   The MSML control interface has been widely deployed in the industry,
   with numerous client-side and server-side implementations, since
   2003.  The in-service commercial deployments cover a wide variety of
   applications including, but not limited to, IP multimedia
   conferencing, network voice services, IVR, IVVR (interactive voice
   and video response), and voice/video mail.

2.  Glossary

   Media Server: a general-purpose platform for executing real-time
   media processing tasks.  This is a logical function that maps either
   to a single physical device or to a portion of a physical device.

   Media Server Client: an application that originates MSML requests to
   a media server and also referred to as a control agent in this
   specification.

   Network Connection: a participant that represents the termination on
   a media server of one or more RTP [i3] sessions (for example, audio
   and video) associated with a call.  Network connections are
   established and removed using a session establishment protocol such
   as SIP.  An instance of a network connection is independent of MSML
   processing instructions applied to it.





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   Dialog: an automated IVR participant.  Examples of dialogs may be
   announcement players, IVR interfaces, or voice recorders.  Dialogs
   may be defined in MSML or using VoiceXML [n5].

   Conference: an intermediary function that provides multimedia mixing
   and other advanced conferencing services.  This specification
   currently considers conferences with audio and/or video media types,
   but is extensible to other media types.

   Identifier: a name that is used to refer to a specific instance of an
   object on the media server, such as a conference or a dialog.
   Identifiers are composed of one or more terms where each term
   identifies an object class and instance.

   Object: the generic term for a media server entity that terminates,
   originates, or processes media.  This specification defines four
   classes of objects and specifies mechanisms to create them, join them
   together, and destroy them.

   Participant Object: an object in a media server that sources original
   media in a call and/or receives and terminates media in a call.

   Intermediary Object: an object in a media server that acts on media
   within a call for the benefit of the participants.

   Independent Object: an object that can exist on a media server
   independent of other objects.

   Operator: an intermediary transformer that modifies or transforms a
   media stream.  Examples of operators may be audio gain controls,
   video scaling, or voice masking.  MSML defines operators as media
   transform objects, which transform media using operations such as
   gain control, when applied to media streams.

   Media Stream: a single media flow between two objects.  A media
   stream has a media type and may be unidirectional or bidirectional.

3.  MSML SIP Usage

   SIP is used to create and modify media sessions with a media server
   according to the procedures defined in RFC 3261 [n1].  Often, SIP
   third party call control [i4] will be used to create sessions to a
   media server on behalf of end users.  MSML is used to define and
   change the service that a user connected to a media server will
   receive.  MSML clients are application servers, soft-switches, or
   other forms of control agents, and SHOULD have an authorized security
   relationship with the media server.  MSML itself does not define
   authorization mechanisms.



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   MSML transactions are originated based upon events that occur in the
   application domain.  These events may be independent from any media
   or user interaction.  For example, an application may wish to play an
   announcement to a conference warning that its scheduled completion
   time is approaching.  Applications themselves are structured in many
   different ways.  Their structure and requirements contribute to their
   selection of protocols and languages.  To accommodate differing
   application needs, MSML has been designed to be neutral to other
   languages and independent of the transport used to carry it.

   MSML is purposely designed to be transport independent.  In this
   release of the specification, SIP INFO [i5] and SIP Control Framework
   [i11] have been chosen for transport mechanisms for MSML, as
   described in the following sections.

3.1.  SIP INFO

   SIP INVITE and INFO [i5] requests and responses MAY be used to carry
   MSML.  INFO requests allow asynchronous mid-call messages within SIP
   with few additional semantics.  In addition, there are existing
   widely deployed implementations of that method, it aids in initial
   developments that are closely coupled with SIP session establishment,
   and it allows MSML to be directly associated with user dialogs when
   third party call control is used.

   Although INFO is sometimes considered not to be a suitable general-
   purpose transport mechanism for messages within SIP, there have been
   proposals to make it more acceptable.  MSML may evolve to include
   other SIP usage and/or to work with other protocols or as a stand-
   alone protocol established through SIP, in future releases of this
   document.

   MSML supports several models for client interaction.  When clients
   use 3PCC to establish media sessions on behalf of end users, clients
   will have a SIP dialog for each media session.  MSML MAY be sent on
   these dialogs.  However the targets of MSML actions are not inferred
   from the session associated with the SIP dialog.  The targets of MSML
   actions are always explicitly specified using identifiers as
   previously defined.

   An application, after interacting with a user, may want to affect
   multiple objects within a media server.  For example, tones or
   messages are often played to a conference when connections are added
   or removed.  A separate message may also be played to a participant
   as they are joined, or to moderators.  Explicit identifiers, that is,
   not inferred from a transport mechanism, allow these multiple actions
   to be easily grouped into a single transaction sent on any SIP
   dialog.



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   MSML also supports a model of dedicated control associations.  This
   supports decoupled application architectures where a client can
   control media server services without also establishing all of the
   media sessions itself.  Control associations are created using SIP,
   but they do not have any associated media session.  Although
   initially INFO messages will be sent on this SIP dialog, just as with
   dialogs associated with media sessions, it is possible that in the
   future, the SIP dialog will be used to establish a separate control
   session (defined in SDP [n9]) that does not use SIP as the transport
   for MSML messages.

   A media server using MSML also sends asynchronous events to a client
   using MSML scripts in SIP INFO.  Events are sent based on previous
   MSML requests and are sent within the SIP dialog on which the MSML
   request that caused the event to be generated was received.  If this
   dialog no longer exists when the event is generated, the event is
   discarded.

   Events may be generated during the execution of a dialog created by a
   <dialogstart> element.  For example, dialogs can send events based on
   user input.  VoiceXML dialogs, on the other hand, generally interact
   with other servers outside of MSML using HTTP.

   An event is also generated when the execution of a dialog terminates,
   because of either completion or failure.  The exact information
   returned is dependent on the dialog language, the capabilities of the
   dialog execution environment, and what was requested by the dialog.
   Both MSML and VoiceXML [n5] allow information to be returned when
   they exit.  These events may be sent in a SIP INFO or a SIP BYE.  SIP
   BYE is used when the dialog itself specifies that the connection
   should be disconnected, for example, through the use of the
   <disconnect> element.

   Conferences may also generate events based upon their configuration.
   An example of this is the notification of the set of active speakers.

3.2.  SIP Control Framework

   The SIP Control Framework [i11] MAY be used as a transport mechanism
   for MSML.

   The Control Framework provides a generic approach for establishment
   and reporting capabilities of remotely initiated commands.  The
   framework utilizes many functions provided by the Session Initiation
   Protocol (SIP) [n1] for the rendezvous and establishment of a
   reliable channel for control interactions.  Compared to SIP INFO, the





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   SIP Control Framework is a more general-purpose transport mechanism
   and one that is not constrained by limitations of the SIP INFO
   mechanism.

   The Control Framework also introduces the concept of a Control
   Package, which is an explicit usage of the Control Framework for a
   particular interaction set.  This specification has already specified
   a list of packages for MSML to control the media server in many
   aspects, including basic dialog, advanced conferencing, advanced
   dialog, and audit service.  Each of these packages has a unique
   Control Package name assigned in order for MSML to be used with the
   Control Framework.

   This section fulfills the mandatory requirement for information that
   MUST be specified during the definition of a Control Framework
   Package, as detailed in SIP Control Framework [i11].

3.2.1.  Control Framework Package Names

   The Control Framework [i11] requires a Control Package definition to
   specify and register a unique name.

   MSML specification defines Control Package names using a hierarchical
   scheme to indicate the inherited relationship across packages.  For
   example, package "msml-x" is derived from package "msml", and package
   "msml-x-y" is derived from package "msml-x".

   The following is a list of Control Package names reserved by the MSML
   specification.

   "msml": this Control Package supports MSML Core Package as specified
      in section 7.

   "msml-conf": this Control Package supports MSML Conference Core
      Package as specified in section 8.

   "msml-dialog": this Control Package supports MSML Dialog Core Package
      as specified in section 9.6.

   "msml-dialog-base": this Control Package supports MSML Dialog Base
      Package as specified in section 9.7.

   "msml-dialog-group": this Control Package supports MSML Dialog Group
      Package as specified in section 9.8.

   "msml-dialog-transform": this Control Package supports MSML Dialog
      Transform Package as specified in section 9.9.




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   "msml-dialog-speech": this Control Package supports MSML Dialog
      Speech Package as specified in section 9.10.

   "msml-dialog-fax-detect": this Control Package supports MSML Dialog
      Fax Detection Package as specified in section 9.11.

   "msml-dialog-fax-sendrecv": this Control Package supports MSML Dialog
      Fax Send/Receive Package as specified in section 9.12.

   "msml-audit": this Control Package supports MSML Audit Core Package
      as specified in section 10.1.

   "msml-audit-conf": this Control Package supports MSML Audit
      Conference Package as specified in section 10.2.

   "msml-audit-conn": this Control Package supports MSML Audit
      Connection Package as specified in section 10.3.

   "msml-audit-dialog": this Control Package supports MSML Audit Dialog
      Package as specified in section 10.4.

   "msml-audit-stream": this Control Package supports MSML Audit Stream
      Package as specified in section 10.5.

   An application server using the Control Framework as transport for
   MSML MUST use one or multiple package names, depending on the service
   required from the media server.  The package name(s) are identified
   in the "Control-Packages" SIP header that is present in the SIP
   INVITE dialog request that creates the control channel, as specified
   in [i11].  The "Control-Packages" value MAY be re-negotiated via the
   SIP re-INVITE mechanism.

3.2.2.  Control Framework Messages

   The usage of CONTROL, response, and REPORT messages, as defined in
   [i11], by each Control Package defined in MSML is different and
   described separately in the following sections.

      MSML Core Package "msml"

         The application server may send a CONTROL message with a body
         of MSML request using the following elements to the MS:

         <msml>: the root element that may contain a list of child
         elements that request a specific operation.  The child elements
         are defined in extended packages (e.g., "msml-conf" and "msml-
         dialog").  This element is also the root element that contains
         an MSML result and event.



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         <send>: sends an event to the specified recipient within the
         media server.  Specific event types are defined within the
         extended packages.

         The media server replies with a response message containing a
         MSML result using the following elements:

         <result>: reports the results of an MSML transaction.

         The media server MAY send the MSML event to the application
         server, in a REPORT or CONTROL message, using the element
         <event>.  The actual content of the <event> and which Control
         Framework message to use are defined within the extended
         packages.

      MSML Conference Core Package "msml-conf"

         This package extends the MSML Core Package to define a
         framework for creation, manipulation, and deletion of a
         conference.

         The AS can send a CONTROL message with a body of the MSML
         request that contains one or multiple conference-related
         commands to the MS.  The MS then replies with a response
         message with a body of the MSML result to indicate whether or
         not the request has been fulfilled.

         During the lifetime of a conference, whenever an event occurs,
         the media server MAY send CONTROL messages containing MSML
         events to notify the application server.  The application
         server SHOULD reply with a response message with no MSML body
         to acknowledge the event has been received.

         This package does NOT use the REPORT message.

      Dialog Core Package "msml-dialog"

         This package extends the MSML Core Package to define the
         structural framework and abstractions for MSML dialogs.

         The application server MAY send CONTROL messages containing a
         MSML request using the following elements:

         <dialogstart>: instantiate an MSML media dialog on a connection
         or a conference.

         <dialogend>: terminates an MSML dialog.




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         <send>: sends an event and an optional namelist to the dialog,
         dialog group, or dialog primitive.

         <exit>: used by the dialog description language to cause the
         execution of the MSML dialog to terminate.

         For the <dialogstart> command, the response message MUST
         contain an MSML result that indicates that the dialog has been
         started successfully.  The MSML result MAY contain <dialogid>
         to return the dialog identifier, if the identifier was assigned
         by the media server.  Subsequently, zero or more MSML events
         MAY be initiated by the media server in (update) REPORT
         messages to report information gathered during the dialog.
         Finally, an MSML event "msml.dialog.exit" SHOULD be generated
         in a (terminate) REPORT message when the dialog terminates
         (e.g., MSML execution of <exit>).

         For the <dialogend> and <send> commands, the response message
         contains the final MSML result that indicates that the request
         has either been fulfilled or rejected.

      Dialog Base Package "msml-dialog-base"

         This package extends the MSML Dialog Core Package to define a
         set of base functionality for MSML dialogs.  The extension
         defines individual media primitives, including <play>,
         <dtmfgen>, <tonegen>, <record>, <dtmf> and <collect>, to be
         used as child element of <dialogstart>.  This package does not
         change the framework message usage as defined by the MSML
         Dialog Core Package.

      Dialog Transform Package "msml-dialog-transform"

         This package extends the MSML Dialog Core Package to define a
         set of transform primitives that works as filter on half-duplex
         media streams.  The extension defines transform primitives,
         including <vad>, <gain>, <agc>, <gate>, <clamp> and <relay>,
         that MAY be used as child elements of <dialogstart>.  This
         package does not change the framework message usage as defined
         by the MSML Dialog Core Package.

      Dialog Group Package "msml-dialog-group"

         This package extends the MSML Dialog Core, Base, and Transform
         Packages to define a single control flow construct that
         specifies concurrent execution of multiple media primitives.
         The extension defines the <group> element that MAY be used as a
         child element of <dialogstart> to enclose multiple media



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         primitives, such that they can be executed concurrently.  This
         package does not change the framework message usage as defined
         by the MSML Dialog Core Package.

      Dialog Speech Package "msml-dialog-speech"

         This package extends the MSML Dialog Core and MSML Base Package
         to define functionality that MAY be used for automatic speech
         recognition and text to speech.  The extension extends the
         <dialogstart> and the <play> elements.

         For <dialogstart>, it defines a new child element <speech> to
         activate grammars or user input rules associated with speech
         recognition.  For <play>, it defines a new child element <tts>
         to initiate the text-to-speech service.

         This package does not change the framework message usage as
         defined by the MSML Dialog Core Package.

      Dialog Fax Detection Package "msml-dialog-fax-detect"

         This package extends the MSML Dialog Core Package to define
         primitives provide fax detection service.  The extension
         defines a primitive <faxdetect> to be used as a child element
         of <dialogstart>.  This package does not change the framework
         message usage as defined by the MSML Dialog Core Package.

      Dialog Fax Send/Receive Package "msml-dialog-fax-sendrecv"

         This package extends the MSML Dialog Core Package to define
         primitives that allow a media server to provide fax send or
         receive service.  The extension defines new primitives
         <faxsend> and <faxrcv>, to be used as a child element of
         <dialogstart>.  This package does not change the framework
         message usage as defined by the MSML Dialog Core Package.

      Dialog Audit Core Package "msml-audit"

         This package extends the MSML Core Package to define a
         framework for auditing media resource(s) allocated on the media
         server.

         This package follows a simple request/response transaction,
         allowing the application server to send CONTROL messages
         containing MSML <audit> requests.  The media server MUST reply
         with a response message containing the result.  The result is
         contained within the <auditresult> element, returning the
         queried state information.



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         This package does NOT use the REPORT message.

      Dialog Audit Conference Package "msml-audit-conf"

         This package extends the MSML Audit Core Package to define
         conference specific states that MAY be queried via the <audit>
         command and the corresponding response MUST be returned by the
         <auditresult> element.  This package does not change the
         framework message usage as defined by the MSML Audit Core
         Package.

      Dialog Audit Connection Package "msml-audit-conn"

         This package extends the MSML Audit Core Package to define
         connection specific states that MAY be queried via the <audit>
         command and the corresponding response MUST be returned by the
         <auditresult> element.  This package does not change the
         framework message usage as defined by the MSML Audit Core
         Package.

      Dialog Audit Dialog Package "msml-audit-dialog"

         This package extends the MSML Audit Core Package to define
         dialog specific states that MAY be queried via the <audit>
         command and the corresponding response MUST be returned by the
         <auditresult> element.  This package does not change the
         framework message usage as defined by the MSML Audit Core
         Package.

      Dialog Audit Stream Package "msml-audit-stream"

         This package extends the MSML Audit Core Package to define
         stream specific states that MAY be queried via the <audit>
         command and the corresponding response MUST returned by the
         <auditresult> element.  This package does not change the
         framework message usage as defined by the MSML Audit Core
         Package.

3.2.3.  Common XML Support

   The XML schema described in [i11] MUST be supported by all Control
   Packages defined by MSML.  However, the "connection-id" value MUST be
   constructed as defined by MSML (i.e., the identifier MUST contain a
   local dialog tag only, while the SIP Control Framework [i11] requires
   that the "connection-id" contain both local and remote dialog tags).






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3.2.4.  Control Message Body

   A valid CONTROL body message MUST conform to the MSML schema, as
   included in this specification, for the MSML package(s) used.

3.2.5.  REPORT Message Body

   A valid REPORT body message MUST conform to the MSML schema, as
   included in this specification, for the MSML package(s) used.

4.  Language Structure

4.1.  Package Scheme

   The primary mechanism for extending MSML is the "package".  A package
   is an integrated set of one or more XML schemas that define
   additional features and functions via new or extended use of elements
   and attributes.  Each package, except for those defined in the
   current document, is defined in a separate standards document, e.g.,
   an Internet Draft or an RFC.  All packages that extend the base MSML
   functionality MUST include references to the MSML base set of schemas
   provided in the Internet Drafts.  A schema in a package MUST only
   extend MSML; that is, it must not alter the existing specification.

   A particular MSML script will include references to all the schemas
   defining the packages whose elements and attributes it makes use of.
   A particular script MUST reference MSML base and optionally extension
   package(s).  See the IANA Considerations section.

   Each package MUST define its own namespace so that elements or
   attributes with the same name in different packages do not conflict.
   A script using a particular element or attribute MUST prefix the
   namespace name on that element or attribute's name if it is defined
   in a package (as opposed to being defined in the base).

   MSML consists of a core package that provides structure without
   support for any specific feature set.  Additional packages, relying
   on the core package, provide functional features.  Any combination of
   additional packages may be used along with the core package.  The
   following describes the set of MSML packages defined in this
   document.










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           +--------------------------------------------------------+
           |                     MSML Core                          |
           +--------------------------------------------------------+
                 /                           \                 \
             +--------+                   +--------+        +-------+
             | Dialog |                   | Conf   |        | Audit |
             | Core   |                   | Core   |        | Core  |
             +--------+                   +--------+        +-------+
        ________  \_______________________________________      |
        ------------------------------------------------        |
       /         \          \         \          \      \       |
   +------+  +---------+ +------+ +------+ +------+ +-------+   |
   |Dialog|  |Dialog   | |Dialog| |Dialog| |Dialog| |Dialog |   |
   |Base  |  |Transform| |Group | |Speech| |Fax   | |Fax    |   |
   +------+  +---------+ +------+ +------+ |Detect| |Send/  |   |
                                           +------+ |Receive|   |
                                                    +-------+   |
                                        ________________________|
                                        -------------------------
                                       /       \       \         \
                                   +-----+ +-----+ +------+ +------+
                                   |Audit| |Audit| |Audit | |Audit |
                                   |Conf | |Conn | |Dialog| |Stream|
                                   +-----+ +-----+ +------+ +------+


   o MSML Core Package (Mandatory)

      Describes the minimum base framework that MUST be implemented to
      support additional core packages.

   o MSML Conference Core Package (Conditionally Mandatory, for
     Conferencing)

      Describes the audio and multimedia basic and advanced conferencing
      package that MAY be implemented.

   o MSML Dialog Core Package (Conditionally Mandatory, for Dialogs)

      Describes the dialog core package that MUST be implemented for any
      dialog services.  However, systems supporting conferencing only,
      MAY omit support for MSML dialogs.  The MSML Dialog Core Package
      specifies the framework within which additional dialog packages
      are supported.  The MSML Dialog Base Package MUST be supported,
      while all other dialog packages MAY be supported.

      o MSML Dialog Base Package (Conditionally Mandatory, for Dialogs)




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      o MSML Dialog Group Package (Optional)

      o MSML Dialog Transform Package (Optional)

      o MSML Dialog Fax Detection Package (Optional)

      o MSML Dialog Fax Send/Receive Package (Optional)

      o MSML Dialog Speech Package (Optional)

   o MSML Audit Core Package (Conditionally Mandatory, for Auditing)

      Describes the audit core package that MUST be implemented to
      support auditing services.  The MSML audit core package specifies
      the framework within which additional audit packages are
      supported.

      o MSML Audit Conference Package (Conditionally Mandatory, for
        Auditing Conference, Conference Dialog, and Conference Stream)

      o MSML Audit Connection Package (Conditionally Mandatory, for
        Auditing Connection, Connection Dialog, and Connection Stream)

      o MSML Audit Dialog Package (Conditionally Mandatory, for Auditing
        Dialog, and MUST be used with either MSML Audit Conference
        Package or MSML Audit Connection Package)

      o MSML Audit Stream Package (Conditionally Mandatory, for Auditing
        Stream, and MUST be used with either MSML Audit Conference
        Package or MSML Audit Connection Package)

   The formal process for defining extensions to MSML dialogs is to
   define a new package.  The new package MUST provide a text
   description of what extensions are included and how they work.  It
   MUST also define an XML schema file (if applicable) that defines the
   new package (which may be through extension, restriction of an
   existing package, or a specific profile of an existing package).
   Dependencies upon other packages MUST be stated.  For example, a
   package that extends or restricts has a dependency on the original
   package specification.  Finally, the new package MUST be assigned a
   unique name and version.

   The types of things that can be defined in new packages are:

      o  new primitives

      o  extensions to existing primitives (events, shadow variables,
         attributes, content)



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      o  new recognition grammars for existing primitives

      o  new markup languages for speech generation

      o  languages for specifying a topology schema

      o  new predefined topology schemas

      o  new variables / segment types (sets & languages)

      o  new control flow elements

   MSML packages are assembled together to form a specific MSML profile
   that is shared between different implementations.  The base MSML
   dialog profiles that are defined in this document consist of the MSML
   Core Package, MSML Dialog Core Package, MSML Dialog Base Package,
   MSML Dialog Group Package, MSML Transform Package, MSML Fax Packages,
   and the MSML Speech Package.

   MSML extension packages, which define primitives, MUST define the
   following for each primitive within the package:

      o  the function that the primitive performs

      o  the attributes that may be used to tailor its behavior

      o  the events that it is capable of understanding

      o  the shadow variables that provide access to information
        determined as a result of the primitive's operation

   The mechanism used to ensure that a media server and its client share
   a compatible set of packages is not defined.  Currently, it is
   expected that provisioning will be used, possibly coupled with a
   future auditing capability.  Additionally, when used in SIP networks,
   packages could be defined using feature tags and the procedures
   defined for Indicating User Agent Capabilities in SIP [i1] used to
   allow a media server to describe its capabilities to other user
   agents.

4.2.  Profile Scheme

   Not all devices and applications using MSML will need to support the
   entire MSML schema.  For example, a media processing device might
   support only audio announcements, only audio simple conferencing, or
   only multimedia IVR.  It is highly desirable to have a system for
   describing what portion of MSML a particular media processing device
   or control agent supports.



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   The package scheme described earlier allows MSML functionality to be
   functionally grouped, relying on the MSML core package.  This scheme
   allows a portion of the complete MSML specification to be
   implemented, on a per-package basis, and also creates a framework for
   future extension packages.  However, within a given package, in some
   cases, only a subset of the package functionality may be required.
   In order to support subsets of packages, with greater degree of
   granularity than at the package level, a profile scheme is required.

   MSML package profiles would identify a subset of a given MSML package
   with specific definitions of elements and attributes.  Each MSML
   package profile MUST be accompanied by one or more corresponding
   schemas.  To use the examples above, there could be an audio
   announcements profile of the MSML Dialog Base Package, an audio
   simple conferencing profile of the MSML Conference Core Package, and
   a multimedia IVR profile of the MSML Dialog Base Package.

   MSML package profiles MUST be published separately from the MSML
   specification, in one or more standards documents (e.g., Internet
   Drafts or RFCs) dedicated to MSML package profiles.  Profiles would
   not be registered with IANA and any organization would additionally
   be free to create its own profile(s) if required.

5.  Execution Flow

   MSML assumes a model where there is a single control context within a
   media server for MSML processing.  That context may have one or many
   SIP [n1] dialogs associated with it.  It is assumed that any SIP
   dialogs associated with the MSML control context have been
   authorized, as appropriate, by mechanisms outside the scope of MSML.

   A media server control context maintains information about the state
   of all media objects and media streams within a media server.  It
   receives and processes all MSML requests from authorized SIP dialogs
   and receives all events generated internally by media objects and
   sends them on the appropriate SIP dialog.  An MSML request is able to
   create new media objects and streams, and to modify or destroy any
   existing media objects and streams.

   An MSML request may simply specify a single action for a media server
   to undertake.  In this case, the document is very similar to a simple
   command request.  Often, though, it may be more natural for a client
   to request multiple actions at one time, or the client would like
   several actions to be closely coordinated by the media server.
   Multiple MSML elements received in a single request MUST be processed
   sequentially in document order.





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   An example of the first scenario would be to create a conference and
   join it with an initial participant.  An example of the second case
   would be to unjoin one or more participants from a main conference
   and join them to a sidebar conference.  In the first scenario,
   network latencies may not be an issue, but it is simpler for the
   client to combine the requests.  In the second case, the added
   network latency between separate requests could mean perceptible
   audio loss to the participant.

   Each MSML request is processed as a single transaction.  A media
   server MUST ensure that it has the necessary resources available to
   carry out the complete transaction before executing any elements of
   the request.  If it does not have sufficient resources, it MUST
   return a 520 response and MUST NOT execute the transaction.

   The MSML request MUST be checked for well-formedness and validated
   against the schema prior to executing any elements.  This allows XML
   [n2] errors to reported immediately and minimizes failures within a
   transaction and the corresponding execution of only part of the
   transaction.

   Each element is expected to execute immediately.  Elements such as
   <dialogstart>, which take an unpredictable amount of time, are
   "forked" and executed in a separate thread (see MSML Dialog
   Packages).  Once successfully forked, execution continues with the
   element following the </dialogstart>.  As such, MSML does not provide
   mechanisms to sequence or coordinate other operations with dialog
   elements.

   Processing within a transaction MUST stop if any errors occur.
   Elements that were executed prior to the error are not rolled back.
   It is the responsibility of the client to determine appropriate
   actions based upon the results indicated in the response.  Most
   elements MAY contain an optional "mark" attribute.  The value of that
   attribute from the last successfully executed element MUST be
   returned in an error response.  Note that errors that occur during
   the execution of a dialog occur outside the context of an MSML
   transaction.  These errors will be indicated in an asynchronous
   event.

   Transaction results are returned as part of the SIP request response.
   The transaction results indicate the success or failure of the
   transaction.  The result MUST also include identifiers for any
   objects created by a media server for which the client did not
   provide an instance name.  Additionally, if the transaction fails,
   the reason for the failure MUST be returned, as well as an indication
   of how much of the transaction was executed before the failure
   occurred SHOULD be returned.



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6.  Media Server Object Model

   Media servers are general-purpose platforms for executing real-time
   media processing tasks.  These tasks range in complexity from simple
   ones such as serving announcements, to complex ones, such as speech
   interfaces, centralized multimedia conferencing, and sophisticated
   gaming applications.

   Calls are established to a media server using SIP.  Clients will
   often use SIP third party call control (3PCC) [i4] to establish calls
   to a media server on behalf of end users.  However MSML does not
   require that 3PCC be used, only that the client and the media server
   share a common identifier for the call and its associated RTP [i3]
   sessions.

   Objects represent entities that source, sink, or modify media
   streams.  A media streams is a bidirectional or unidirectional media
   flow between objects on a media server.  The following subsections
   define the classes of objects that exist on a media server and the
   way these are identified in MSML.

6.1.  Objects

   A media object is an endpoint of one or more media streams.  It may
   be a connection that terminates RTP sessions from the network or a
   resource that transforms or manipulates media.  MSML defines four
   classes of media objects.  Each class defines the basic properties of
   how object instances are used within a media server.  However, most
   classes require that the function of specific instances be defined by
   the client, using MSML or other languages such as VoiceXML.

   The following classes of media processing objects are defined.  The
   class names are given in parentheses:

      o network connection (conn)

      o conference (conf)

      o dialog (dialog)

   Network connection is an abstraction for the media processing
   resources involved in terminating the RTP session(s) of a call.  For
   audio services, a connection instance presents a full-duplex audio
   stream interface within a media server.  Multimedia connections have
   multiple media streams of different media types, each corresponding
   to an RTP session.  Network connections get instantiated through SIP
   [n1].




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   A conference represents the media resources and state information
   required for a single logical mix of each media type in the
   conference (e.g., audio and video).  MSML models multiple mixes/views
   of the same media type as separate conferences.  Each conference has
   multiple inputs.  Inputs may be divided into classes that allow an
   application to request different media treatment for different
   participants.  For example, the video streams for some participants
   may be assigned to fixed regions of the screen while those for other
   participants may only be shown when they are speaking.

   A conference has a single logical output per media type.  For each
   participant, it consists of the audio conference mix, less any
   contributed audio of the participant, and the video mix shared by all
   conference participants.  Video conferences using voice activated
   switching have an optional ability to show the previous speaker to
   the current speaker.

   Conferences are instantiated using the <createconference> element.
   The content of the <createconference> element specifies the
   parameters of the audio and/or video mixes.

   Dialogs are a class of objects that represent automated participants.
   They are similar to network connections from a media flow perspective
   and may have one or more media streams as the abstraction for their
   interface within a media server.  Unlike connections, however,
   dialogs are created and destroyed through MSML, and the media server
   itself implements the dialog participant.  Dialogs are instantiated
   through the <dialogstart> element.  Contents of the <dialogstart>
   element define the desired or expected dialog behavior.  Dialogs may
   also be invoked by referencing VoiceXML as the dialog description
   language.

   Operators are functions that are used to filter or transform a media
   stream.  The function that an instance of an operator fulfills is
   defined as a property of the media stream.  Operators may be
   unidirectional or bidirectional and have a media type.
   Unidirectional operators reflect simple atomic functions such as
   automatic gain control, filtering tones from conferences, or applying
   specific gain values to a stream.  Unidirectional operators have a
   single media input, which is connected to the media stream from one
   object, and a single media output, which is connected to the media
   stream of a different object.

   Bidirectional operators have two media inputs and two media outputs.
   One media input and output is associated with the stream to one
   object, and the other input and output is associated with a stream to
   a different object.  Bidirectional objects may treat the media
   differently in each direction.  For example, an operator could be



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   defined that changed the media sent to a connection based upon
   recognized speech or dual-tone multi-frequency (DTMF) received from
   the connection.  Operators are implicitly instantiated when streams
   are created or modified using the elements <join> and <modifystream>,
   respectively.

   The relationships between the different object classes (conf, conn,
   and dialog) are shown in the figure below.

              +--------------------------------------+
              |           Media Server               |
              |                                      |
              |------+                      ,---.    |
              |      |      +------+       /     \   |
   <== RTP ==>| conn |<---->| oper |<---->( conf  )  |
              |      |      +------+       \     /   |
              |------+                      `---'    |
              |   ^                           ^      |
              |   |                           |      |
              |   |   +------+    +------+    |      |
              |   |   |      |    |      |    |      |
              |   +-->|dialog|    |dialog|<---+      |
              |       |      |    |      |           |
              |       +------+    +------+           |
              +--------------------------------------+

   A single, full-duplex instance of each object class is shown together
   with common relationships between them.  An operator (such as gain)
   is shown between a connection and a conference and dialogs are shown
   participating both with an individual connection and with a
   conference.  The figure is not meant to imply only one-to-one
   relationships.  Conferences will often have hundreds of participants,
   and either connections or conferences may be interacting with more
   than one dialog.  For example, one dialog may be recording a
   conference while other dialogs announce participants joining or
   leaving the conference.

6.2.  Identifiers

   Objects are referenced using identifiers that are composed of one or
   more terms.  Each term specifies an object class and names a specific
   instance within that class.  The object class and instance are
   separated by a colon ":" in an identifier term.

   Identifiers are assigned to objects when they are first created.  In
   general, either the MSML client or a media server may specify the
   instance name for an object.  Objects for which a client does not
   assign an instance name will be assigned one by a media server.



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   Media server assigned instance names are returned to the client as a
   complete object identifier in the response to the request that
   created the object.

   It is meaningful for some classes of objects to exist independently
   on a media server.  Network connections may be created through SIP at
   any time.  MSML can then be used to associate their media with other
   objects as required to create services.  Conferences may be created
   and have specific resources reserved waiting for participant
   connections.

   Objects from these two classes, connections and conferences, are
   considered independent objects since they can exist on a standalone
   basis.  Identifiers for independent objects consist of a single term
   as defined above.  For example, identifiers for a conference and
   connection could be "conf:abc" or "conn:1234" respectively.  Clients
   that choose to assign instance names to independent objects must use
   globally unique instance names.  One way to create globally unique
   names is to include the domain name of the client as part of the
   name.

   Dialogs are created to provide a service to independent objects.
   Dialogs may act as a participant in a conference or interact with a
   connection similar to a two-participant call.  Dialogs depend upon
   the existence of independent objects, and this is reflected in the
   composition of their identifiers.  Operators modify the media flow
   between other objects, such as application of gain between a
   connection and a conference.  As operators are merely media transform
   primitives defined as properties of the media stream, they are not
   represented by identifiers and created implicitly.

   Identifiers for dialogs are composed of a structured list of slash
   ('/') separated terms.  The left-most term of the identifier must
   specify a conference or connection.  This serves as the root for the
   identifier.  An example of an identifier for a dialog acting as a
   conference participant could be:

      conf:abc/dialog:recorder

   All objects except connections are created using MSML.  Connections
   are created when media sessions get established through SIP.  There
   are several options clients and media servers can use to establish a
   shared instance name for a connection and its media streams.

   When media servers support multiple media types, the instance name
   SHOULD be a call identifier that can be used to identify the
   collection of RTP sessions associated with a call.  When MSML is used
   in conjunction with SIP and third party call control, the call



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   identifier MUST be the same as the local tag assigned by the media
   server to identify the SIP dialog.  This will be the tag the media
   server adds to the "To" header in its response to an initial invite
   transaction.  RFC 3261 requires the tag values to be globally unique.

   An example of a connection identifier is: conn:74jgd63956ts.

   With third party call control, the MSML client acts as a back-to-back
   user agent (B2BUA) to establish the media sessions.  SIP dialogs are
   established between the client and the media server allowing the use
   of the media server local tag as a connection identifier.  If third
   party call control is not used, a SIP event package MAY be used to
   allow a media server to notify new sessions to a client that has
   subscribed to this information.

   Identifiers as described above allow every object in a media server
   to be uniquely addressed.  They can also be used to refer to multiple
   objects.  There are two ways in which this can currently be done:

      wildcards

      common instance names

   An identifier can reference multiple objects when a wildcard is used
   as an instance name.  MSML reserves the instance name composed of a
   single asterisk ('*') to mean all objects that have the same
   identifier root and class.  Instance names containing an asterisk
   cannot be created.  Wildcards MUST only be used as the right-most
   term of an identifier and MUST NOT be used as part of the root for
   dialog identifiers.  Wildcards are only allowed where explicitly
   indicated below.

   The following are examples of valid wildcards:

      conf:abc/dialog:*

      conn:*

   An example of illegal wildcard usage is:

      conf:*/dialog:73849

   Although identifiers share a common syntax, MSML elements restrict
   the class of objects that are valid in a given context.  As an
   example, although it is valid to join two connections together, it is
   not valid to join two IVR dialogs.





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7.  MSML Core Package

   This section describes the core MSML package that MUST be supported
   in order to use any other MSML packages.  The core MSML package
   defines a framework, without explicit functionality, over which
   functional packages are used.

7.1.  <msml>

   <msml> is the root element.  When received by a media server, it
   defines the set of operations that form a single MSML request.
   Operations are requested by the contents of the element.  Each
   operation MAY appear zero or more times as children of <msml>.
   Specific operations are defined within the conference package and in
   the set of dialog packages.

   The results of a request or the contents of events sent by a media
   server are also enclosed within the <msml> element.  The results of
   the transaction are included as a body in the response to the SIP
   request that contained the transaction.  This response will contain
   any identifiers that the media server assigned to newly created
   objects.  All messages that a media server generates are correlated
   to an object identifier.  Objects and identifiers are discussed in
   section 6 (Media Server Object Model).

   Attributes:

      version: "1.1" Mandatory

7.2.  <send>

   Events are used to affect the behavior of different objects within a
   media server.  The <send> element is used to send an event to the
   specified recipient within the media server.

   Attributes:

      event: the name of an event.  Mandatory.

      target: an object identifier.  When the identifier is for a
      dialog, it may optionally be appended with a slash "/" followed by
      the target to be included in an MSML dialog <send>.  Mandatory.

      valuelist: a list of zero or more parameters that are included
      with the event.






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      mark: a token that can be used to identify execution progress in
      the case of errors.  The value of the mark attribute from the last
      successfully executed MSML element is returned in an error
      response.  Therefore, the value of all mark attributes within an
      MSML document should be unique.

7.3.  <result>

   The <result> element is used to report the results of an MSML
   transaction.  It is included as a body in the final response to the
   SIP request that initiated the transaction.  An optional child
   element <description> may include text that expands on the meaning of
   error responses.  Response codes are defined in section 11 (Response
   Codes).

   Attributes:

      response: a numeric code indicating the overall success or failure
      of the transaction, and in the case of failure, an indication of
      the reason.  Mandatory.

      mark: in the case of an error, the value of the mark attribute
      from the last successfully executed element that included the mark
      attribute.

   In the case of failure, a description of the reason SHOULD be
   provided using the child element <description>.

   Three other child elements allow the response to include identifiers
   for objects created by the request but that did not have instance
   names specified by the client.  Those elements are <confid> and
   <dialogid>, for objects created through a <createconference> and
   <dialogstart> respectively.

7.4.  <event>

   The <event> element is used to notify an event to a media server
   client.  Three types of events are defined by the MSML Core Package:
   "msml.dialog.exit", "msml.conf.nomedia", and "msml.conf.asn".  These
   correspond to the termination of an executing dialog, a conference
   being automatically deleted when the last participant has left, and
   the notification of the current set of active speakers for a
   conference, respectively.  Events may also be generated by an
   executing dialog.  In this case, the event type is specified by the
   dialog (see MSML Dialog Core Package <send>).






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   Attributes:

      name: the type of event.  If the event is generated because of the
      execution MSML dialog <send>, the value MUST be the value of the
      "event" attribute from the <send> element within the MSML Dialog
      Core Package.  If the event is generated because of the execution
      of an <exit>, the value MUST be "moml.exit".  If the event is
      generated because of the execution of a <disconnect>, the value
      MUST be "moml.disconnect".  If the event is generated because of
      an error, the value must be "moml.error".  Mandatory.

      id: the identifier of the conference or dialog that generated the
      event or caused the event to be generated.  Mandatory.

      <event> has two children, <name> and <value>, which contain the
      name and value respectively of each namelist item associated with
      the event.

8.  MSML Conference Core Package

8.1.  Conferences

   A conference has a mixer for each type of media that the conference
   supports.  Each mix has a corresponding description that defines how
   the media from participants contributes to that mix.  A mixer has
   multiple inputs that are combined in a media specific way to create a
   single logical output.

   The elements that describe the mix for each media type are called
   mixer description elements.  They are:

   <audiomix> defines the parameters for mixing audio media.

   <videolayout> defines the composition of a video window.

   These elements, defined in sections 8.6 (Audio Mix) and 8.7 (Video
   Layout) respectively, are used as content of the <createconference>
   element to establish the initial properties of a conference.  The
   elements are used within the <modifyconference> element to change the
   properties of a conference once it has been created, or within the
   <destroyconference> element to remove individual mixes from the
   conference.

   Conferences may be terminated by an MSML client using the
   <destroyconference> element to remove the entire conference or by
   removing the last mixer(s) associated with the conference.
   Conferences can also be terminated automatically by a media server
   based on criteria specified when the conference is created.  When the



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   conference is deleted, any remaining participants will have their
   associated SIP dialogs left unchanged or deleted based on the value
   of the "term" attribute specified when the conference was created.

8.2.  Media Streams

   Objects have at least one media input and output for each type of
   media that they support.  Each object class defines the number of
   input and output objects of that class support.  Media streams are
   created when objects are joined, either explicitly using <join> or
   implicitly when dialogs are created using <dialogstart>.  Dialog
   creation has two stages, allocating and configuring the resources
   required for the dialog instance, and implicitly joining those
   resources to the dialog target during the dialog execution.  Refer to
   the MSML Dialog Base Package.

   A join operation by default creates a bidirectional audio stream
   between two objects.  Video and unidirectional streams may also be
   created.  A media stream is created by connecting the output from one
   object to the input of another object and vice versa (assuming a
   bidirectional or full-duplex join).

   Many objects may only support a single input for each type of media.
   Within this specification, only the conference object class supports
   an arbitrary number of inputs.  When a stream is requested to be
   created to an object that already has a stream of the same type
   connected to its single input, the result of the request depends upon
   the type of the media stream.

   Audio mixing is done by summing audio signals.  Automatically mixing
   audio streams has common and straightforward applications.  For
   example, the ability to bridge two streams allows for the easy
   creation of simple three-way calls or to bridge private announcements
   with a (whispered) conference mix for an individual participant.  In
   the case of general conferences, however, an MSML client SHOULD
   create an audio conference and then join participants to the
   conference.  Conference mixers SHOULD subtract the audio of each
   participant from the mix so that they do not hear themselves.

   A media server receiving a request that requires joining an audio
   stream to the single audio input of an object that already has an
   audio stream connected SHOULD automatically bridge the new stream
   with the existing stream, creating a mix of the two audio streams.
   The maximum number of streams that may be bridged in this manner is
   implementation specific.  It is RECOMMENDED that a media server
   support bridging at least two streams.  A media server that cannot
   bridge a new stream with any existing streams MUST fail the operation
   requesting the join.



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   Unlike audio mixing, there are many different ways that two video
   streams may be combined and presented.  For example, they may be
   presented side by side in separate panes, picture in picture, or in a
   single pane that displays only a single stream at a time based on a
   heuristic such as active speaker.  Each of these options creates a
   very different presentation and requires significantly different
   media resources.

   A join operation does not describe how a new stream can be combined
   with an existing stream.  Therefore, automatic bridging of video is
   not supported.  A media server MUST fail requests to join a new video
   stream to an object that only supports a single video input and
   already has a video stream connected to that input.  For an object to
   have multiple video streams joined to it, the object itself must be
   capable in supporting multiple video streams.  Conference objects can
   support multiple video streams and provide a way to specify the
   mixing presentation for the video streams.

   A media server MUST NOT establish any streams unless the media server
   is able to create all the streams requested by an operation.  Streams
   are only able to be created if both objects support a media type and
   at least one of the following conditions is true:

      1. Each object that is to receive media is not already receiving a
         stream of that type.

      2. Any object that is to receive media and is already receiving a
         stream of that type supports receiving an additional stream of
         that type.  The only class of objects defined in this
         specification that directly support receiving multiple streams
         of the same type are conferences.

      3. The media server is able to automatically bridge media streams
         for an object that is to receive media and that is already
         receiving a stream of the requested type.  The only type of
         media defined in this specification that MAY be automatically
         bridged is audio.

   The directionality of media streams associated with a connection is
   modeled independently from what SDP [n9] allows for the corresponding
   RTP [i3] sessions.  Media servers MUST respect the SDP in what they
   actually transmit but MUST NOT allow the SDP to affect the
   directionality when joining streams internal to the media server.








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8.3.  <createconference>

   <createconference> is used to allocate and configure the media mixing
   resources for conferences.  A description of the properties for each
   type of media mix required for the conference is defined within the
   content of the <createconference> element.  Mixer descriptions are
   described in Audio Mix and Video Layout sections.  When no mixer
   descriptions are specified, the default behavior MUST be equivalent
   to inclusion of a single <audiomix>.

   Clients can request that a media server automatically delete a
   conference when a specified condition occurs by using the
   "deletewhen" attribute.  A value of "nomedia" indicates that the
   conference MUST be deleted when no participants remain in the
   conference.  When this occurs, an "msml.conf.nomedia" event MUST be
   notified to the MSML client.  A value of "nocontrol" indicates that
   the conference MUST be deleted when the SIP [n1] dialog that carries
   the <createconference> element is terminated.  When this occurs, a
   media server MUST terminate all participant dialogs by sending a BYE
   for their associated SIP dialog.  A value of "never" MUST leave the
   ability to delete a conference under the control of the MSML client.

   Attributes:

      name: the instance name of the conference.  If the attribute is
      not present, the media server MUST assign a globally unique name
      for the conference.  If the attribute is present but the name is
      already in use, an error (432) will result and MSML document
      execution MUST stop.  Events that the conference generates use
      this name as the value of their "id" attribute (see section 7.4
      (<event>)).

      deletewhen: defines whether a media server should automatically
      delete the conference.  Possible values are "nomedia",
      "nocontrol", and "never".  Default is "nomedia".

      term: when true, the media server MUST send a BYE request on all
      SIP dialogs still associated with the conference when the
      conference is deleted.  Setting term equal to false allows clients
      to start dialogs on connections once the conference has completed.
      Default is "true".

      mark: a token that MAY be used to identify execution progress in
      the case of errors.  The value of the mark attribute from the last
      successfully executed MSML element is returned in an error
      response.  Therefore, the value of all mark attributes within an
      MSML document should be unique.




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   An example of creating an audio conference is shown below.  This
   conference allows at most two participants to contend to be heard and
   reports the set of active speakers no more frequently than every 10
   seconds.

      <?xml version="1.0" encoding="UTF-8"?>
      <msml version="1.1">
         <createconference name="example">
            <audiomix>
               <n-loudest n="3"/>
               <asn ri="10s"/>
            </audiomix>
         </createconference>
      </msml>

8.3.1.  <reserve>

   Conference resources may be reserved by including the <reserve>
   element as a child of <createconference>.  <reserve> allows the
   specification of a set of resources that a media server will reserve
   for the conference.  Any requests for resources beyond those that
   have been reserved should be honored on a best-effort basis by a
   media server.

   Attributes:

      required: boolean that specifies whether <createconference> should
      fail if the requested resources are not available.  When set to
      false, the conference will be created, with no reserved resources,
      if the complete reservation cannot be honored.  Default is "true".

8.3.1.1.  <resource>

   The resources to be reserved are defined using <resource>.  The
   contents of these elements describe a resource that is to be
   reserved.  Descriptions are implementation dependent.  Media servers
   that support MSML dialogs may use the elements from that package as
   the basis for resource descriptions.  Each resource element may use
   the attribute "n" to define the quantity of the resource to reserve.

   For example, the following creates a conference and reserves two
   types of resources.  One resource element may represent resources
   that are shared by all participants of the conference, while the
   other may represent resources that are reserved for each of the
   expected participants.






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   Attributes:

      n: number of resources to be reserved.  Default is 1.

      type: specifies whether the resource is to be reserved by each
      individual participant or reserved as a shared conference
      resource.  Valid values for this attribute are "individual" or
      "shared".  Default is "individual".

      <createconference>
         <reserve>
            <resource n="20">
              <!--description of resources used by each participant-->
            </resource>
            <resource n="2" type="shared">
              <!--description of the shared conference resources-->
            </resource>
         </reserve>
      </createconference>

8.4.  <modifyconference>

   All of the properties of an audio mix or the presentation of a video
   mix may be changed during the life of a conference using the
   <modifyconference> element.  Changes to an audio mix are requested by
   including an <audiomix> element as a child of <modifyconference>.
   This may also be used to add an audio mixer to the conference if none
   was previously allocated.  Changes to a video presentation are
   requested by including a <videolayout> element as a child of
   <modifyconference>.  Similar to an audio mixer, this may be used to
   add a video mixer if none was previously allocated.

   Mixers are removed by including a mixer description element within
   <destroyconference/>.

   Features and presentation aspects are enabled/added or modified by
   including the element(s) that define the feature or presentation
   aspect within a mixer description.  The complete specification of the
   element must be included just as it would be included when the
   conference is created.  The new definition completely replaces any
   previous definition that existed.  Only things that are defined by
   elements included in the mixer descriptions are affected.  Any
   existing configuration aspects of a conference, which are not
   specified within the <modifyconference/> element, MUST maintain their
   current state in the media server.






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   For example, if an MSML client wanted to change the minimum reporting
   interval for active speaker notification from that shown in the
   Conference Examples section (<createconference>) it would send the
   following to the media server:

      <?xml version="1.0" encoding="UTF-8"?>
      <msml version="1.1">
         <modifyconference id="conf:example">
            <audiomix>
               <asn ri="4"/>
            </audiomix>
         </modifyconference>
      </msml>

   This would also enable active speaker notification if it had not
   previously been enabled.  The N-loudest mixing is unaffected.

   Multiple elements MAY be included in the mixer descriptions similar
   to when conferences are created.  For example, in a video conference,
   the video mix description (<videolayout>) could specify that the
   layout of the video being displayed should change such that the
   regions currently displaying participants get smaller and new
   region(s) are created to support additional participants.  A media
   server MUST make all of the requested changes or none of the
   requested changes.

   Additional examples of modifying conferences are presented in the
   Conference Examples section.

   Attributes:

      id: the identifier for a conference.  Wildcards MUST NOT be used.
      Mandatory.

      mark: a token that can be used to identify execution progress in
      the case of errors.  The value of the mark attribute from the last
      successfully executed MSML element is returned in an error
      response.  Therefore, the value of all "mark" attributes within an
      MSML document SHOULD be unique.

8.5.  <destroyconference>

   Destroy conference is used to delete mixers or to delete the entire
   conference and all state and shared resources.  When a mixer is
   removed, all of the streams joined to that mixer are unjoined.  When
   a conference is destroyed, SIP dialogs for any remaining participants
   MUST be maintained or removed based on the value of the "term"
   attribute when the conference was created.



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   When there is no element content, <destroyconference/> deletes the
   entire conference.  Individual mixers are removed by including a
   mixer description element identifying the mix (or mixes) to be
   removed as content to <destroyconference/>.  <audiomix/> is used
   remove audio mixers and <videolayout/> is used remove video mixers.
   When one or more mixer descriptions are specified, then media server
   MUST only delete the specified mixer and MUST NOT affect any other
   existing mixers.  When <audiomix/> or <videolayout/> is identified
   for individual removal, other feature aspects of the mix MUST NOT be
   included.  If specified, the media server MUST ignore any such
   elements.  When the last mixer is removed from a conference, a media
   server MUST remove all conference state, leaving or removing any
   remaining SIP dialogs as described above.

   Attributes:

      id: the identifier for a conference.  Mandatory.

      mark: a token that can be used to identify execution progress in
      the case of errors.  The value of the mark attribute from the last
      successfully executed MSML element is returned in an error
      response.  Therefore, the value of all "mark" attributes within an
      MSML document SHOULD be unique.

8.6.  <audiomix>

   The properties of the overall audio mix are specified using the
   <audiomix> element.

   Attributes:

      id: an optional identifier for the audio mix.

      samplerate: Integer value specifies the sample rate (in Hz) for
      the audio mixer.  Optional, default value of 8000.

   An example of the description for an audio mix is:

      <audiomix id="mix1">
        <asn ri="10s"/>
        <n-loudest n="3"/>
      </audiomix>

8.6.1.  <n-loudest>

   The <n-loudest> element defines that participants contend to be
   included in the conference mix based upon their audio energy.  When
   the element is not present, all participants are mixed.



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   Attributes:

      n: the number of participants that will be included in the audio
      mix based upon having the greatest audio energy.  Mandatory.

8.6.2.  <asn>

   The <asn> element enables notification of active speakers.  Active
   speakers MUST be notified using the <event> element with an event
   name of "msml.conf.asn".  The namelist of the event consists of the
   set of active speakers.  The name of each item is the string
   "speaker" with a value of the connection identifier for the
   connection.

   Attributes:

      ri: the minimum reporting interval defines the minimum duration of
      time that must pass before changes to active speakers will be
      reported.  A value of zero disables active speaker notification.

      asth: specifies the active speaker threshold (in unit of dBm0).
      Valid value range is 0 to -96.  Optional, default is -96.

   An example of an active speaker notification is:

      <event name="msml.conf.asn" id="conf:example">
         <name>speaker</name>
         <value>conn:hd93tg5hdf</value>
         <name>speaker</name>
         <value>conn:w8cn59vei7</value>
         <name>speaker</name>
         <value>conn:p78fnh6sek47fg</value> </event>

8.7.  <videolayout>

   A video layout is specified using the <videolayout> element.  It is
   used as a container to hold elements that describe all of the
   properties of a video mix.  The parameters of the window that
   displays the video mix are defined by the <root> element.  When the
   video mix in composed of multiple panes, the location and
   characteristics of the panes are defined by one or more <region>
   elements.  A <region> element is not required when only a single
   video stream is displayed at one time and none of the visual
   attributes of regions are required.

   Some regions may be used to display a video stream based on a
   selection criteria rather than having a video stream of a single
   participant continuously presented in the region.  One such an



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   example is a distance learning lecture where the instructor sees each
   of the students periodically displayed in a region.  When a region is
   used to display one of a number of streams, it is placed as a child
   of a <selector> element.

   Attributes:

      type: specifies the language used to define the layout.  Layouts
      defined using MSML MUST use the value "text/msml-basic-layout".
      This is the same convention as defined for the layout package from
      the W3C SMIL 2.0 specification [i6].  The default when omitted is
      "text/msml-basic-layout".

      id: an optional identifier for the video layout.

8.7.1.  <root>

   The <root> element describes the root window or virtual screen in
   which the conference video mix will be displayed.  Simple conferences
   can display participant video directly within the root window but
   more complex conferences will use regions for this purpose.  Areas of
   the window which are not used to display video will show the root
   window background.

   All video presentations require a root window.  It MUST be present
   when a video mix is created and it cannot be deleted; however, its
   attributes MAY be changed using the <modifyconference> element.

   Attributes:

      size: the size of the root window specified as one of the five
      standard common intermediate formats (e.g., CIF, QCIF).

      backgroundcolor: the color for the root window background defined
      using the values for the "background-color" property of the CSS2
      specification [n10].

      backgroundimage: the URI for an image to be displayed as the root
      window background.  Transparent portions of the image allow the
      background color to show through.

8.7.2.  <region>

   <region> elements define video panes that are used to display
   participant video streams.  Regions are rendered on top of the root
   window.





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   The size of a region is specified relative to the size of the root
   window using the "relativesize" attribute.  Relative sizes are
   expressed as fractions (e.g., 1/4, 1/3) that preserve the aspect
   ratio of the original video stream while allowing for efficient
   scaling implementations.

   Regions are located on the root window based on the value of the
   position attributes "top" and "left".  These attributes define the
   position of the top left corner of the region as an offset from the
   top left corner of the root window.  Their values may be expressed
   either as a number of pixels or as a percent of the vertical or
   horizontal dimension of the root window.  Percent values are appended
   with a percent ('%') character.  Percent values of "33%" and "67%"
   should be interpreted as "1/3" and "2/3" to allow easy alignment of
   regions whose size is expressed relative to the size of the root
   window.

   An example of a video layout with six regions is:

      +-------+---+
      |       | 2 |
      |   1   +---+
      |       | 3 |
      +---+---+---+
      | 6 | 5 | 4 |
      +---+---+---+

      <videolayout type="text/msml-basic-layout">
         <root size="CIF"/>
         <region id="1" left="0" top="0" relativesize="2/3"/>
         <region id="2" left="67%" top="0" relativesize="1/3"/>
         <region id="3" left="67%" top="33%" relativesize="1/3">
         <region id="4" left="67%" top="67%" relativesize="1/3"/>
         <region id="5" left="33%" top="67%" relativesize="1/3"/>
         <region id="6" left="0" top="67%" relativesize="1/3"/>
      </videolayout>

   The area of the root window covered by a region is a function of the
   region's position and its size.  When areas of different regions
   overlap, they are layered in order of their "priority" attribute.
   The region with the highest value for the "priority" attribute is
   below all other regions and will be hidden by overlapping regions.
   The region with the lowest non-zero value for the "priority"
   attribute is on top of all other regions and will not be hidden by
   overlapping regions.  The priority attribute may be assigned values
   between 0 and 1.  A value of zero disables the region, freeing any
   resources associated with the region, and unjoining any video stream
   displayed in the region.



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   Regions that do not specify a priority will be assigned a priority by
   a media server when a conference is created.  The first region within
   the <videolayout> element that does not specify a priority will be
   assigned a priority of one, the second a priority of two, etc.  In
   this way, all regions that do not explicitly specify a priority will
   be underneath all regions that do specify a priority.  As well,
   within those regions that do not specify a priority, they will be
   layered from top to bottom, in the order they appear within the
   <videolayout> element.

   For example, if a layout was specified as follows:

      <videolayout>
         <root size="CIF"/>
         <region id="a" ... priority=".3" .../>
         <region id="b" ... />
         <region id="c" ... priority=".2" ...>
         <region id="d" ... />
      </videolayout>

   Then the regions would be layered, from top to bottom, c,a,b,d.

   Portions of regions that extend beyond the root window will be
   cropped.  For example, a layout specified as:

      <videolayout>
         <root size="CIF"/>
         <region id="foo" left="50%" top="50%" relativesize="2/3"/>
      </videolayout>

   would appear similar to:

      +-----------+
      |   root    |
      |background |
      |     +-----+--
      |     |     |//
      |     | foo |//
      +-----+-----+//
            |////////

   Visual attributes are used to define aspects of the visual appearance
   of individual regions.  A border may be defined together with a title
   and/or logo.  Text and logos are displayed as images on top of the
   region's video, below all regions with a lower priority.  The visual
   attributes are "title", "titletextcolor", "titlebackgroundcolor",
   "bordercolor", "borderwidth", and "logo".




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   Visual attributes can also be defined for individual streams (Video
   Stream Properties).  When visual attributes are specified as part of
   both a region and a stream, those associated with the stream MUST
   take precedence.  This allows streams that are chosen for display
   automatically (Stream Selection) to have proper text and logos
   displayed.  The region visual attributes are displayed when no stream
   is associated with the region.

   Two other attributes associated with a region, "blank" and "freeze",
   define the state of the video displayed in the region.  When the
   blank or freeze attribute is assigned the value "true", then the
   media server MUST display the region either as a blank region, or the
   video image frozen at the last received frame.

   These attributes are specified for a region and not allowed for
   streams because that appears to be the common use case.  Applying
   them to streams would allow only that stream to be affected within a
   selector while other streams continue to display normally.  Except
   for personal mixing scenarios, the same effect can be achieved by
   having the participant mute their own transmission to the media
   server.

   Attributes: associated with each region:

      id: a name that can be used to refer to the region.

      left: the position of the region from the left side of the root
      window.

      top: the position of the region from the top of the root window.

      relativesize: the size of the region expressed as a fraction of
      the root window size.

      priority: a number between 0 and 1 that is used to define the
      precedence when rendering overlapping regions.  A value of zero
      disables the region.

      title: text to be displayed as the title for the region

      titletextcolor: the color of the text

      titlebackgroundcolor: the color of the text background

      bordercolor: the color of the region border

      borderwidth: the width of the region border




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      logo: the URI of an image file to be displayed

      freeze: a boolean value, with a default of "false", that defines
      whether the video image should be frozen at the currently
      displayed frame

      blank: a boolean value, with a default of "false", that defines
      whether the region should display black instead of the associated
      video stream

8.7.3.  <selector>

   It is often desired that one of several video streams be
   automatically selected to be displayed.  The <selector> element is
   used to define the selection criteria and its associated parameters.
   The selection algorithm is specified by the "method" attribute.
   Currently defined selection methods allow for voice activated
   switching and to iterate sequentially through the set of associated
   video streams.

   The regions that will display the selected video stream are placed as
   child elements of the <selector> element.  Including regions within a
   <selector> element does not affect their layout with respect to
   regions not subject to the selection.  For simple video conferences
   that display the video directly in the root window, the <root>
   element can be placed as a child of <selector>.  Region elements MUST
   NOT be used in this case.

   For example, below is a common video layout that allows the video
   stream from the currently active speaker to be displayed in the large
   region ("1") at the top left of the layout while the streams from
   five other participants are displayed in regions located at the
   layout periphery.

      +-------+---+
      |       | 2 |
      |   1   +---+
      |       | 3 |
      +---+---+---+
      | 6 | 5 | 4 |
      +---+---+---+










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      <videolayout type="text/msml-basic-layout">
         <root size="CIF"/>
         <selector id="switch" method="vas">
            <region id="1" left="0" top="0" relativesize="2/3"/>
         </selector>
         <region id="2" left="67%" top="0" relativesize="1/3"/>
         <region id="3" left="67%" top="33%" relativesize="1/3">
         <region id="4" left="67%" top="67%" relativesize="1/3"/>
         <region id="5" left="33%" top="67%" relativesize="1/3"/>
         <region id="6" left="0" top="67%" relativesize="1/3"/>
      </videolayout>

   All selector methods must be defined so that they work if only a
   single region is a child of the selector.  Selector methods that
   support more than one child region MUST specify how the method works
   across multiple regions.  Media server implementations MAY support
   only a single region for methods that are defined to allow multiple
   regions.

   The selector or region for a participant's video is defined using the
   "display" attribute of <stream> during a join operation.  Specifying
   a selector allows the stream to be displayed according to the
   criteria defined by the selector method.  Specifying a region
   supports continuous presence display of participants.  Some streams
   may be joined with both a selector and a region.  In this case, the
   value of <blankothers> attribute defines whether the streams
   associated with a continuous presence region should be blanked when
   the stream is selected for display in one of the selector regions.

   Attributes: common to all selector methods are:

      id: a name that can be used to refer to the selector.

      method: the name of the method used to select the video stream.  A
      value of "vas" (see the following section, Voice Activated
      Switching) MAY be specified.

      status: specifies whether the selector is "active" or "disabled".

      blankothers: when "true", video streams that are also displayed in
      continuous presence regions will have the continuous presence
      regions blanked when the stream is displayed in a selection
      region.








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8.7.3.1.  Voice Activated Switching ("vas")

   Voice activated switching (VAS) is used to display the video stream
   that correlates with the participant who is currently speaking.  It
   is specified using a selector method value of "vas".

   If the video stream associated with the active speaker is not
   currently displayed in a selection region, then it replaces the video
   in the region that is displaying the video of the speaker that was
   least recently active.  If the video of the active speaker is
   currently displayed in a selection region, then there is no change to
   any region.  When VAS is applied to a single region, this has the
   effect that the current speaker is displayed in that region.

   Attributes:

      si: switching interval is the minimum period of time that must
      elapse before allowing the video to switch to the active speaker.

      speakersees: defines whether the active speaker sees the "current"
      speaker (themselves) or the "previous" speaker.

8.8.  <join>

   <join> is used to create one or more streams between two independent
   objects.  Streams may be audio or video and may be bidirectional or
   unidirectional.  A bidirectional stream is implicitly composed of two
   unidirectional streams that can be manipulated independently.  The
   streams to be established are specified by <stream> elements (section
   <stream>) as the content of <join>.

   Without any content, <join> by default establishes a bidirectional
   audio stream.  When only a stream of a single type has previously
   been created between two objects, or when only a unidirectional
   stream exists, <join> can be used to add a stream of another media
   type or make the stream bidirectional by including the necessary
   <stream> elements.  Bidirectional streams are made unidirectional by
   using <unjoin> (section <unjoin>) to remove the unidirectional stream
   for the direction that is no longer required.

   In addition to defining the media type and direction of streams,
   <stream> elements are also used to establish the properties of
   streams, such as gain, voice masking, or tone clamping of audio
   streams, or labels and other visual characteristics of video streams.
   Properties are often defined asymmetrically for a single direction of
   a stream.  Creating a bidirectional stream requires two <stream>
   elements within the <join>, one for each direction, if one direction
   is to have different properties from the other direction.



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   If a media server can provide services using both compressed or
   uncompressed media, the MSML client may need to distinguish within
   requests which format is to be used.  When compressed streams are
   created, both objects must use the same media format or an error
   response (450) is generated.

   Attributes:

      id1: an identifier of either a connection or conference.
      Wildcards MUST NOT be used.  Mandatory.  Any other object class
      results in a 440 error.

      id2: an identifier of either a connection or conference.
      Wildcards MUST NOT be used.  Mandatory.  Any other object class
      results in a 440 error.

      mark: a token that can be used to identify execution progress in
      the case of errors.  The value of the mark attribute from the last
      successfully executed MSML element is returned in an error
      response.  Therefore, the value of all mark attributes within an
      MSML document SHOULD be unique.

   For example, consider a call center coaching scenario where a
   supervisor can listen to the conversation between an agent and a
   customer and provide hints to the agent, which are not heard by the
   customer.  One join establishes a stream between the agent and the
   customer and another join establishes a stream between the agent and
   the supervisor.  A third join is used to establish a half-duplex
   stream from the customer to the supervisor.  The media server
   automatically bridges the media streams from the customer and the
   supervisor for the agent, and from the customer and the agent for the
   supervisor.

   Assuming the following connections, each with a single audio stream:

      conn:supervisor

      conn:agent

      conn:customer











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   The following would create the media flows previously described:

      <?xml version="1.0" encoding="UTF-8"?>
      <msml version="1.1">
         <join id1="conn:supervisor" id2="conn:agent"/>
         <join id1="conn:agent" id2="conn:customer"/>
         <join id1="conn:supervisor" id2="conn:customer">
            <stream media="audio" dir="to-id1"/>
         </join>
      </msml>

      The following example shows joining a participant to a multimedia
      conference.  It assumes that the conference has a video
      presentation region named "topright".  The "display" attribute is
      explained in the section Video Stream Properties.

      <?xml version="1.0" encoding="UTF-8"?>
      <msml version="1.1">
         <join id1="conn:hd83t5hf7g3" id2="conf:example">
            <stream media="audio"/>
            <stream media="video" dir="from-id1" display="topright"/>
            <stream media="video" dir="to-id1"/>
         </join>
      </msml>

8.9.  <modifystream>

   Media streams can have different properties such as the gain for an
   audio stream or a visual label for a video stream.  These properties
   are specified as the content of <stream> elements (section <stream>).
   <modifystream> is used to change the properties of a stream by
   including one or more <stream> elements that are to have their
   properties changed.

   Stream properties MUST be set as specified by the element <stream> as
   a child element of <modifystream> element.  Any properties not
   included in the <stream> element when modifying a stream MUST remain
   unchanged.  Setting a property for only one direction of a
   bidirectional stream MUST NOT affect the other direction.  The
   directionality of streams can be changed by issuing an <unjoin>
   followed by a <join>.  Any streams that exist between the two objects
   that are not included within <modifystream> MUST NOT be affected.

   Attributes:

      id1: an identifier of either a conference or a connection.  The
      instance name MUST NOT contain a wildcard if "id2" contains a
      wildcard.  Mandatory.



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      id2: an identifier of either a conference or a connection.  The
      instance name MUST NOT contain a wildcard if "id1" contains a
      wildcard.  Mandatory.

      mark: a token that can be used to identify execution progress in
      the case of errors.  The value of the mark attribute from the last
      successfully executed MSML element is returned in an error
      response.  Therefore, the value of all mark attributes within an
      MSML document is RECOMMENDED to be unique.

8.10.  <unjoin>

   Unjoin removes one or more media streams between two objects.  In the
   absence of any content in the <stream> element, all media streams
   between the objects MUST be removed.  Individual streams may be
   removed by specifying them using <stream> elements, while the
   unspecified streams MUST NOT be removed.  A bidirectional stream is
   changed to a unidirectional stream by unjoining the direction that is
   no longer required, using the <unjoin> element.  Operator elements
   MUST NOT be specified within <stream> elements when streams are being
   unjoined using the <unjoin> element.  Any specified stream operators
   MUST be ignored.

   <unjoin> and <join> may be used together to move a media stream, such
   as from a main conference to a sidebar conference.

   Attributes:

      id1: an identifier of either a conference or a connection.  The
      instance name MUST NOT contain a wildcard if "id2" contains a
      wildcard.  Mandatory.

      id2: an identifier of either a conference or a connection.  The
      instance name MUST NOT contain a wildcard if "id1" contains a
      wildcard.  Mandatory.

      mark: a token that can be used to identify execution progress in
      the case of errors.  The value of the mark attribute from the last
      successfully executed MSML element is returned in an error
      response.  Therefore, the value of all mark attributes within an
      MSML document SHOULD be unique.

   The following removes a participant from a conference and plays a
   leave tone for the remaining participants in the conference.







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      <?xml version="1.0" encoding="UTF-8"?>
      <msml version="1.1">
         <unjoin id1="conn:jd73ht89sf489f" id2="conf:1"/>
         <dialogstart target="conf:1" type="application/moml+xml">
            <play>
               <audio uri="file://leave_tone.wav"/>
            </play>
         </dialogstart>
      </msml>

8.11.  <monitor>

   Monitor is a specialized unidirectional join that copies the media
   that is destined for a connection object.  One example of the use for
   <monitor> may be quality monitoring within a conference.  The media
   stream may be removed using the <unjoin> element (see the section
   <unjoin>).

   Attributes:

      id1: an identifier of the connection to be monitored.  Mandatory.
      Any other object class results in a 440 error.  Wildcards MUST NOT
      be used.

      id2: an identifier of the object that is to receive the copy of
      the media destined to id1.  id2 may be a connection or a
      conference.  Mandatory.  Any other object class results in a 440
      error.  Wildcards MUST NOT be used.

      compressed: "true" or "false".  Specifies whether the join should
      occur before or after compression.  When "true", id2 must be a
      connection using the same media format as id1 or an error response
      (450) is generated.  Default is "false".

      mark: a token that can be used to identify execution progress in
      the case of errors.  The value of the mark attribute from the last
      successfully executed MSML element is returned in an error
      response.  Therefore, the value of all mark attributes within an
      MSML document SHOULD be unique.

8.12.  <stream>

   Individual streams are specified using the <stream> element.  They
   MAY be included as a child element in any of the stream manipulation
   elements <join>, <modifystream>, or <unjoin>.






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   The type of the stream is specified using a "media" attribute that
   uses values corresponding to the top-level MIME media types as
   defined in RFC 2046 [i7].  This specification only addresses audio
   and video media.  Other specifications may define procedures for
   additional types.

   A bidirectional stream is identified when no direction attribute
   "dir" is present.  A unidirectional stream is identified when a
   direction attribute is present.  The "dir" attribute MUST have a
   value of "from-id1" or "to-id1" depending on the required direction.
   These values are relative to the identifier attributes of the parent
   element.

   The compressed attribute is used to distinguish the compressed nature
   of the stream when necessary.  It is implementation specific what is
   used when the attribute is not present.  Joining compressed streams
   acts much like an RTP [i3] relay.

   The properties of the media streams are specified as the content of
   <stream> elements when the element is used as a child of <join> or
   <modifystream>.  Stream elements MUST NOT have any content when they
   are used as a child of <unjoin> to identify specific streams to
   remove.

   Some properties are defined within MSML as additional attributes or
   child elements of <stream> that are media type specific.  Ones for
   audio streams and video streams are defined in the following two sub-
   sections.  Operators, viewed as properties of the media stream, MAY
   be specified as child elements of the <stream> element.

   Attributes:

      media: "audio" or video".  Mandatory

      dir: "from-id1" or "to-id1".

      compressed: "true" or "false".  Specifies whether the stream uses
      compressed media.  Default is implementation specific.

8.12.1.  Audio Stream Properties

   Audio mixes can be specified to only mix the N-loudest participants.
   However, there may be some "preferred" participants that are always
   able to contribute.  When audio streams are joined to a conference
   that uses N-loudest audio mixing, preferred streams need to be
   identified.





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   A preferred audio stream is identified using the "preferred"
   attribute.  The "preferred" attribute MAY be used for an audio stream
   that is input to a conference and MUST NOT be used for other streams.

   Additional attributes of the <stream> element for audio streams are:

   Attributes:

      preferred: a boolean value that defines whether the stream does
      not contend for N-loudest mixing.  A value of "true" means that
      the stream MUST always be mixed while a value of "false" means
      that the stream MAY contend for mixing into a conference when
      N-loudest mixing is enabled.  Default is "false".

   There are two elements that can be used to change the characteristics
   of an audio stream as defined below.

8.12.1.1.  <gain>

   The <gain> element may be used to adjust the volume of an audio media
   stream.  It may be set to a specific gain amount, to automatically
   adjust the gain to a desired target level, or to mute the stream.

   Attributes:

      id: an optional identifier that may be referenced elsewhere for
      sending events to the gain primitive.

      amt: a specific gain to apply specified in dB or the string "mute"
      indicating that the stream should be muted.  This attribute MUST
      NOT be used if "agc" is present.

      agc: boolean indicating whether automatic gain control is to be
      used.  This attribute MUST NOT be used if "amt" is present.

      tgtlvl: the desired target level for AGC specified in dBm0.  This
      attribute MUST be specified if "agc" is set to "true".  This
      attribute MUST NOT be specified if "agc" is not present.

      maxgain: the maximum gain that AGC may apply.  Maxgain is
      specified in dB.  This attribute MUST be used if "agc" is present
      and MUST NOT be used when "agc" is not present.

8.12.1.2.  <clamp>

   The <clamp> element is used to filter tones and/or audio-band dtmf
   from a media stream.




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   Attributes:

      dtmf: boolean indicating whether DTMF tones should be removed.

      tone: boolean indicating whether other tones should be removed.

8.12.2.  Video Stream Properties

   Video mixes define a presentation that may have multiple regions,
   such as a quad-split.  Each region displays the video from one or
   more participants.  When video streams are joined to such a
   conference, the region that will display the video needs to be
   specified as part of the join operation.

   The region that will display the video is specified using the
   "display" attribute.  The "display" attribute MUST be used for a
   video stream that is input to a conference and MUST NOT be used for
   other streams.  The value of the attribute MUST identify a <region>
   (see the section <region>) or a <selector> (see the section
   <selector>) that is defined for the conference.  A stream MUST NOT be
   directly joined to a region that is defined within a selector.
   Changing the value of the "display" attribute can be used to change
   where in a video presentation layout a video stream is displayed.

   Additional attributes of the <stream> element for video streams are:

   Attributes:

      display: the identifier of a video layout region or selector that
      is to be used to display the video stream.

      override: specifies whether or not the given video stream is the
      override source in the region defined by "display" attribute.
      Valid values are "true" or "false".  Optional, default value is
      "false".  Only a video stream that is input to a conference can be
      the override source.  A particular region can have at most one
      override source at a time.  The most recently joined video stream
      with this attribute set to "true" becomes the override source.
      When there's an override source in place, its video is always
      displayed in the region, regardless of what video selection
      algorithm (either a selector or continuous presence mode) is
      configured for that region.  Once the override source is cleared,
      the conference MUST revert back to original video selection
      algorithm.







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8.12.2.1.  <visual>

   Some regions of video conferences may display different streams
   automatically, such as when voice activated switching is used.
   Connections MAY also be joined directly without the use of video
   mixing.  In these cases, the <visual> element may be used to define
   visual display properties for a stream.

   The <visual> element MAY use any of the visual attributes defined for
   regions (see the section <region>).  This allows the visual aspects
   of regions within a <selector> to be tailored to the selected video
   stream, or for streams that are directly joined to display a name or
   logo.

9.  MSML Dialog Packages

9.1.  Overview

   MSML Dialog Packages define an XML [n2] language for composing
   complex media objects from a vocabulary of simple media resource
   objects called primitives.  It is primarily a descriptive or
   declarative language to describe media processing objects.  MSML
   dialogs operate on a single or multiple streams that are identified
   by the MSML document outside the scope of the MSML Dialog Package.

   MSML dialogs are intended to be used in different environments.  As
   such, the language itself does not define how an MSML dialog is used.
   Each environment in which an MSML dialog is used must define how it
   is used, the set of services provided, and the mechanism for passing
   information between the environment and MSML dialog.  The specific
   mechanisms used to realize the interface between MSML dialog and its
   environment are platform specific.

   MSML Dialog Packages provide two models for access to media resources
   and service creation building blocks.  Both models MAY be used in
   conjunction with each other in a complementary manner.  The first
   model (referred to as "Media Primitives and Composites", part of the
   mandatory MSML Dialog Base Package) contains media primitives (such
   as digit collection and announcements) and composite functions (such
   as play and collect combined as a single operation).  The second
   model (referred to as "Media Groups", part of the optional MSML
   Dialog Group Package) allows the ability to define complex customized
   interactions, via event passing mechanisms, between media primitives,
   if required.







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      MSML Dialog Core Package

         Defines core framework over which all MSML Dialog Packages
         operate.

      MSML Dialog Base Package

         Media Primitives
            <dtmf> or <collect>
                        DTMF digit collection
            <play>
                        Playing of Announcements
            <dtmfgen>
                        Generation of DTMF digits
            <tonegen>
                        Tone genration
            <record>
                        Media recording

         Media Composites
            <collect>
                        Supports play and collect operation.
                        Composite function with inclusion of play.
            <record>
                        Supports play and record operation.
                        Composite function with inclusion of play.

      MSML Dialog Group Package
            <group>
                        Allows grouping of media primitives for parallel
                        execution, with an event exchange mechanism
                        between the media primitives to achieve
                        customized media operations. All the above media
                        primitive elements are accepted within the
                        group.

   The following operations MUST be supported using elements described
   above using either the MSML Dialog Base Package or MSML Dialog Group
   Package.

      Announcement only
                        <play>
            Collection only
                        <dtmf> or <collect>

            Recording only
                        <record>




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            Play and Collect
                        <collect>
                           <play/>
                        </collect>

            Play and Record
                        <record>
                           <play/>
                        </record>

   Additional MSML Dialog Packages are:

      o MSML Dialog Transform Package

      o MSML Dialog Speech Package

      o MSML Fax Detection Package

      o MSML Fax Send/Receive Package

   MSML dialogs MAY be used to simply expose primitive media resource
   objects but will be used more often to describe dialog operations and
   media transformation objects that can be controlled via user
   interaction.

   MSML dialogs do not contain any computation or flow control
   constructs.  There are no results automatically generated when media
   operations complete.  Results MUST be explicitly requested using a
   <send> or <exit> element within the definition of the MSML dialog.

9.2.  Primitives

   Primitives perform a single function on a media stream or multiple
   streams such as generating audio/video, recognizing speech or DTMF,
   or adjusting the gain.  They may be composed so that primitives
   execute concurrently.  Primitives not composed for concurrent
   execution MUST simply execute sequentially in the order they occur in
   an MSML document.  All concurrently executing primitives in the same
   MSML object (defined in one MSML document) MAY interact with each
   other through events (see MSML Dialog Group Package).

   Primitives are categorized into one of the following descriptive
   categories.

      o  Recognizers have a media input but no output.  They allow
         different things within a media stream to be recognized or
         detected and for events to be generated based upon received
         media.



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      o  Transformers have one media input and output and may send and
         receive events.

      o  Sources and sinks generate or consume media.  They have either
         a media input or a media output but not both.  They may receive
         and generate events.

      o  Composites combine underlying primitives to provide higher-
         level user interaction, without the need for specific event-
         based exchange between the primitives.  The composite elements
         provide a simpler mechanism for more commonly used services,
         such as play and collect or play and record.

   Primitives may define different media processing behavior (states)
   based upon the events that they receive.  Primitives that support
   different processing states must define their default starting state
   and should support the "initial" attribute to allow that state to be
   specified when the primitive is instantiated.  All primitives must
   support the "terminate" event class.

   The following types of primitives are defined within this
   specification:

      Recognizers    Transformers   Source/Sink   Composites
      ------------------------------------------------------
       dtmf/collect   agc            play          dtmf/collect
       faxdetect      clamp          record        record
       speech         gain           dtmfgen
       vad            gate           tonegen
                      relay          faxsend
                                     faxrcv

   Primitives have shadow variables, similar to those within VoiceXML
   [n5], which are automatically assigned values when the primitives are
   used.  Upon initialization of an MSML dialog context, all shadow
   variables have the string value "undefined".  Each primitive has its
   own instance of shadow variables that are global in scope to the
   entire MSML dialog context.

   Names SHOULD be assigned to individual primitives when more than one
   primitive of the same type is used within one MSML document.  Shadow
   variables are overwritten if the primitive has not been named and is
   instantiated a second time.

   Shadow variables cannot be modified under user control.  They may be
   returned from the MSML dialog context using the <send> element.





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9.3.  Events

   Events provide the mechanism for primitives to interact with each
   other and for an MSML context to interact with its external
   environment.  The external environment is defined by the way in which
   an MSML context has been invoked.  This will often be through MSML,
   but other languages and protocols such as SIP may also be used.

   Every primitive and group conceptually implements their own event
   queue.  Events sent to them get placed into their associated queue.
   Events are removed from their queues and processed in order.
   Primitives within a group conceptually have their own thread of
   execution.  Due to the asynchronous nature of servicing events from
   multiple queues, it cannot be assumed that several events sent in
   sequence to different queues will be processed in the order in which
   they were sent.  For example, if recognition of something led to
   sending events to both a <play> and a <record> in that order, it is
   possible that the <record> may process its event before the <play>.

   Primitives each define the set of events that they support and the
   behavior associated with their handling of each event.  This allows
   many types of behaviors to be defined.  For example, VCR type
   controls can be constructed by defining primitives that support
   events corresponding to each control.  Media recognition/detection
   can be used to cause those events to be generated.

   Alternatively, events can be originated elsewhere, such as from a
   control agent, and simply received by the primitive implementing the
   control.  Examples of the use of events include adjusting volume
   (gain) and pause and resume of both announcement playout and record
   creation.

   Primitives act on events based upon the longest match of an event
   name.  Event names are a period '.' delimited sequence of tokens.
   The first token, or the root of the name, can be considered an event
   class.  Matching allows a standard meaning to be defined and then
   extended based upon what triggers an event's generation.  For
   example, a record primitive has different behavior depending upon
   whether it completed because a user stopped speaking or because it
   was cancelled.  The recording is retained in the first case but not
   the second.

   Longest match allows new recognizers to be created and used without
   changing how existing primitives are defined.  For example, a face
   recognition capability could be created that generates a
   terminate.frowning event when a user looks puzzled.  Although no
   primitive directly defines this event, it will still effect a generic
   terminate action.  Primitives that require specialized behavior based



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   upon frowning may be extended to support this.  As well, the event
   can still be exported from the MSML context without requiring that
   primitives receiving the event understand facial expressions.

9.4.  MSML Dialog Usage with SIP

   MSML dialogs MAY be used directly with SIP for dialog interactions
   (e.g., IVR or fax).  It can be initially invoked as part of the
   "Prompt and Collect" service described in "Basic Network Media
   Services with SIP" [n7].  That defines service indicators for a small
   number of well-defined services using the user part of the SIP
   Request-URI (R-URI).

   The prompt and collect service uses "dialog" as the service
   indicator.  URI parameters further refine the specific IVR request.
   This document defines an additional parameter "msml-param" for the
   dialog service indicator as follows:

   dialog-parameters = ";" ( dialog-param [ vxml-parameters ] )
                           | moml-param
   dialog-param      = "voicexml=" dialog-url
   moml-param        = "moml=" moml-url

   There are no additional URI parameters when MSML is used as the
   dialog language.

   MSML dialogs define discrete IVR dialog commands.  These commands MAY
   be included directly in the body of the INVITE to the "dialog"
   service indicator by using the "cid" [n8] URL scheme.  This scheme
   identifies a message body part that in this case would contain the
   MSML dialog request.  Note that a multipart message body, containing
   a single part, MUST be present even if the INVITE does not contain an
   SDP offer.  Subsequent MSML dialog requests are sent in the body of
   SIP INFO messages as are all messages from a media server.

   An example of SIP URI as described above is:

      sip:dialog@mediaserver.example.net;\
          moml=cid:14864099865376@appserver.example.net

   The body part that contained the MSML dialog referenced by the URL
   would have a Content-Id header of:

      Content-Id: <14864099865376@appserver.example.net>







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   The results of executing an <exit> or <disconnect>, or of executing a
   <send> that has a "target" attribute value equal to "source", are
   notified in SIP INFO messages using the <event> element from MSML
   Core package.  No messages are sent if execution completes normally
   without executing one of these elements.

   If there is an error during validation or execution, then a media
   server MUST notify the error as described above and must include the
   namelist items "moml.error.status" and "moml.error.description".  The
   values for these items are defined in section 11.

   A restricted subset of MSML dialogs can also be used with the
   "Announcement" service defined in [n7].  This service uses "annc" as
   the service indicator and defines parameters that describe an
   announcement.  The "play=" parameter identifies the URL of a prompt
   or a provisioned announcement sequence.  The value of the "play="
   parameter can refer to an MSML dialog body part using a "cid" URL as
   described above.  That body part must only contain the <play>
   primitive.

   Using MSML dialogs enhances the announcement service by allowing the
   client to specify a sequence of audio segments rather than requiring
   each sequence to be provisioned as well as support for video.
   Moreover, MSML dialogs define a standard set of variables in contrast
   to [n7] which defines a parameterization mechanism but does not
   formally specify any semantics.

   If a media server does not understand the "cid" scheme or does not
   understand MSML dialogs, it must respond with the SIP response code
   "488 - not acceptable here".  If the MSML dialog body contains
   elements other than the <play> primitive, or there are errors during
   validation, a media server must respond with a SIP response code "400
   - bad request".  Finally, if there is a discrepancy between
   parameters specified in the Request-URI and corresponding attributes
   defined in the MSML dialog body, the Request-URI parameters must be
   silently ignored.

   MSML dialogs MUST NOT change the operation of the announcement
   service from that defined in [n7].  When the announcement completes,
   a media server issues a SIP BYE request.  The INFO method MUST NOT
   used with the announcement service.

9.5.  MSML Dialog Structure and Modularity

   MSML is structured as a set of packages.  Only the core and base
   packages are required.  The Dialog Core Package defines the framework
   for MSML requests to a media server, without specific functionality.
   It consists of the "primitive" abstraction, an abstract element for



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   control flow, the sequential execution model, and the <send> element.
   That is, the MSML Dialog Core Package allows for the execution of a
   sequence of one or more media processing primitives with the ability
   to notify events to the invocation environment.

   Primitives are contained within the MSML Dialog Base Package, which
   defines the basic <play>, <record>, <dtmf>, <dtmfgen>, <tonegen>, and
   <collect> elements.  Another package, the MSML Dialog Transform
   Package, defines the simple half-duplex filters.  More advanced
   primitives are defined in the speech and fax packages.  The MSML
   speech package depends on the MSML Dialog Base Package as it extends
   the capability of <play> by adding synthesized speech.  Finally, the
   group execution model, which is currently the only element that
   changes the flow of control, is defined in a separate MSML Dialog
   Group Package.  All of these packages are optional with the exception
   that MSML Dialog Core and MSML Dialog Base Packages MUST be
   implemented to provide the minimal functionality.

9.6.  MSML Dialog Core Package

   The MSML Dialog Core Package defines the structural framework and
   abstractions for MSML dialogs (via its schema).  It also defines the
   basic elements that are not part of the core primitive or control
   abstractions.  This package is dependent on the MSML Core Package.
   Events generated by MSML dialogs, such as prompt completion, digits
   collected, or dialog termination, are communicated by the media
   server via the MSML Core Package (see MSML Core Package <event>).

   MSML dialogs are executed independently from the MSML core context.
   When an MSML dialog is started, MSML allocates the dialog control
   resources, and if successful, starts those resources executing.  MSML
   core execution then continues without waiting for the MSML dialog to
   complete.  This forking of MSML dialog invocation from the MSML core
   context is done via the <dialogstart> element.  Media streams are
   created between the MSML dialog target and other internal media
   server resources as part of dialog execution.  Stream creation is
   subject to the requirements defined in the MSML Core Package and
   media streams as defined by the MSML Conference Core Package.

9.6.1.  <dialogstart>

   The <dialogstart> element is used to instantiate an MSML media dialog
   on connections or conferences.  The dialog is specified either inline
   or by a URI [n6].  Inline dialogs MUST be composed of any of the MSML
   Dialog Packages.  MSML dialogs MAY be defined externally as VoiceXML
   [n5].  The MSML dialog description MUST NOT be inline if the src
   attribute, containing a URI, is present.




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   The originator of the MSML dialog is notified using a
   "msml.dialog.exit" event when the dialog completes.  Any results
   returned by the dialog when it exits are sent as a namelist to the
   event.

   The "msml.dialog.exit" event is also used when dialogs fail due to
   errors encountered fetching external documents or errors that occur
   within the dialog execution thread.  In this case, a namelist
   containing the items "dialog.exit.status" and
   "dialog.exit.description" is returned with the event to inform the
   client of the failure and the failure reason.  The values of these
   items are defined within this package and the MSML Core Package.
   Information from the failed dialog may be returned as additional
   namelist items.

   Attributes:

      target: an identifier of a connection or a conference that will
      interact with the dialog.  The identifier must not contain
      wildcards.  Mandatory.

      src: the URL of the dialog description.  MUST NOT be used if the
      MSML dialog description is inline.  Otherwise, an error (422) will
      result and MSML document execution will stop.

      type: a MIME type that identifies the type of language used to
      describe the dialog.  application/moml+xml and
      application/vxml+xml are used to identify MSML dialogs and
      VoiceXML [n5] respectively.  Mandatory.

      name: an instance name for the dialog.  If the attribute is not
      present, the media server will assign an identifier to the dialog.
      If the attribute is present but the name is already associated
      with the target, an error (431) will result and MSML document
      execution will stop.  Any results that a dialog generates will be
      correlated to its identifier.

      mark: a token that can be used to identify execution progress in
      the case of errors.  The value of the mark attribute from the last
      successfully executed MSML element is returned in an error
      response.  Therefore, the value of all "mark" attributes within an
      MSML document should be unique.

   The following sections show examples of initiating an external MSML
   dialog, an inline embedded MSML dialog, and an MSML-initiated
   VoiceXML dialog.

   The following example starts an MSML dialog on a connection.



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      <?xml version="1.0" encoding="UTF-8"?>
      <msml version="1.1">
         <dialogstart target="conn:abcd1234"
               type="application/moml+xml"
               name="sample"
               src="http://server.example.com/scripts/foo.moml"/>
       </msml>

   The following example starts an inline embedded MSML dialog on a
   connection.

      <?xml version="1.0" encoding="UTF-8"?>
      <msml version="1.1">
        <dialogstart target="conn:abcd1234" name="sample">
           <play>
              <audio uri="file://clip1.wav"/>
              <audio uri="http://host1/clip2.wav"/>
              <tts uri="http://host2/text.ssml"/>
              <var type="date" subtype="mdy" value="20030601"/>
           </play>
           <send target="source"
                  event="done"
                  namelist="play.amt play.end"/>
         </dialogstart>
      </msml>

   The following example starts a VoiceXML dialog on a connection.

      <?xml version="1.0" encoding="UTF-8"?>
      <msml version="1.1">
         <dialogstart target="conn:abcd1234"
             type="application/vxml+xml"
             name="sample"
             src="http://server.example.com/scripts/foo.vxml"/>
      </msml>

   If this dialog fails once its execution thread had begun, for
   example, the fetch of the VoiceXML document failed, an example of the
   event that would be returned would be:

      <?xml version="1.0" encoding="UTF-8"?>
      <event name="msml.dialog.exit"
             id="conn:abcd1234/dialog:sample">
         <name>dialog.exit.status</name>
         <value>423</value>
         <name>dialog.exit.description</name>
         <value>External document fetch error</value>
      </event>



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9.6.2.  <dialogend>

   Dialog end is used to terminate an MSML dialog created through
   <dialogstart> before it completes of its own accord.  The operation
   of <dialogend> depends on the dialog language being used by the
   executing context.  When that context is VoiceXML, a
   "connection.disconnected" event will be thrown to the VoiceXML
   application.  When that context is MSML dialog, a "terminate" event
   will be sent to the MSML core context.

   <dialogend> allows the executing dialog the opportunity to gracefully
   complete before generating a "msml.dialog.exit" event.  Dialog
   results may be returned and will be contained as a namelist to that
   event.

   Attributes:

      id: the identifier of a dialog.  Mandatory.

      mark: a token that can be used to identify execution progress in
      the case of errors.  The value of the mark attribute from the last
      successfully executed MSML dialog element is returned in an error
      response.  Therefore, the value of all "mark" attributes within an
      MSML document should be unique.

   For example, if the dialog from the previous example was still
   executing, the following would terminate the dialog and generate an
   "msml.dialog.exit" event.

      <?xml version="1.0" encoding="UTF-8"?>
      <msml version="1.1">
         <dialogend id="conn:abcd1234/dialog:sample"/>
      </msml>

9.6.3.  <send>

   The <send> element sends an event and optional namelist to the
   recipient identified by the target attribute.  Event names are
   defined by the recipient.  In the case where the recipient is an MSML
   dialog group or primitive, the events are defined within this
   document.  Other recipients MAY use names that are suitable for their
   environment.

   The "target" attribute specifies the recipient of the event.
   Recipients MAY be other MSML dialog primitives or groups executing
   within the object, the object itself, or the environment that invoked
   the MSML dialog.  Sending events to media primitives or groups is
   supported by the MSML Dialog Group Package.  Any target that is



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   unknown within the object is assumed to be destined to the external
   environment.  By convention, the string "source" SHOULD used to
   address that environment, but any target name distinct from the MSML
   dialog namespace MAY be used.

   Attributes:

      event: the name of an event.  Mandatory.

      target: the recipient of the event.  The recipient MUST be a MSML
      dialog primitive, the currently executing group, or the MSML
      dialog environment.  A primitive is specified by a primitive type,
      optionally appended by a period '.' followed by the identifier of
      a primitive.  Identifiers are only needed when more than one
      primitive of the same type exists in the object.  The executing
      group is specified using the token "group".  The environment is
      specified using the token "source", optionally appended by a
      period '.' followed by any environment specific target.
      Mandatory.

      namelist: a list of zero or more shadow variables that are
      included with the event.

9.6.4.  <exit>

   The <exit> element causes execution of the MSML dialog to terminate.

   Attributes:

      namelist: a list of one or more shadow variables that MAY
      optionally be sent to the context that invoked the MSML Dialog
      object.

9.6.5.  <disconnect>

   The <disconnect> element is similar to <exit> but has the additional
   semantics of indicating to the context that invoked the MSML dialog
   that it should disconnect from a media server, the media stream
   associated with the object.  The method of disconnection depends upon
   how the media stream was initially established.  If SIP was used, a
   <disconnect> would cause a media server to issue a BYE request.  The
   request would be sent for the SIP dialog associated with media
   session on which the MSML dialog was operating.








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   Attributes:

      namelist: a list of one or more shadow variables that MAY
      optionally be sent to the context that invoked the MSML dialog
      object.

9.7.  MSML Dialog Base Package

   The MSML Dialog Base Package defines a required set of base
   functionality for the media server.  It supports individual media
   primitives, such as playing an announcement or collection digits, as
   well as composite operations such as play and collect.  When this
   package is used in conjunction with the MSML Dialog Group Package,
   the event-based mechanism is used to control primitives.  This
   package may also be used in conjunction with the MSML Speech Package
   to extend the functionality of prompts to include TTS and user input
   collection to include ASR.

   In the following sections, subsections of a primitive define child
   elements of that primitive and are not themselves considered
   primitives.  They do not receive events or populate shadow variables.

9.7.1.  <play>

   Play is used to generate an audio or video stream.  It MUST play in
   sequence the media created by the child media elements <audio>,
   <video>, <media>, <tts>, and <var>.  When the play stops, either
   because the terminate event is received or all media generation has
   completed, the <playexit> element, if present, is executed.  At least
   one media generation element must be present.

   Play supports two states: generate and suspend.  Media generation
   occurs in the generate state and is suspended in the suspend state.
   Once in the suspend state, media generation continues upon receiving
   the generate event.  The default initial state is generate.

   Audio MAY be generated in different languages by specifying the
   xml:lang attribute for <play> and/or the child elements of <play>.
   The language is inherited by the child elements, but each child MAY
   specify its own language.  Except for physical audio clips, it is an
   error if a language is specified but the media server cannot render
   the audio in the requested language.

   Attributes:

      id: an optional identifier that may be referenced elsewhere for
      sending events to the play primitive.




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      interval: specifies the delay between stopping one iteration and
      beginning another.  The attribute has no effect if iterate is not
      also specified.  Default is no interval.

      iterate: specifies the number of times the media specified by the
      child media elements should be played.  Each iteration is a
      complete play of each of the child media elements in document
      order.  Defaults to once '1'.

      initial: defines the initial state for the play element.  Default
      is "generate".

      maxtime: defines the maximum allowed time for the <play> to
      complete.

      barge: defines whether or not audio announcements may be
      interrupted by DTMF detection during play-out.  The DTMF digit
      barging the announcement is stored in the digit buffer.  Valid
      values for barge are "true" or "false", and the attribute is
      mandatory.  When barge is applied to a conference target, DTMF
      digit detected from any conference participant MUST terminate the
      announcement.

      cleardb: defines whether or not the digit buffer is cleared, prior
      to starting the announcement.  Valid values for cleardb are "true"
      or "false", and the attribute is mandatory.

      offset: defines an offset, measured in units of time, where the
      <play> is to begin media generation.  Offset is only valid when
      all child media elements are <audio>.

      skip: an amount, expressed in time, that will be used to skip
      through the media when "forward" and "backward" events are
      received.  Default is 3 s (three seconds).

      xml:lang: specifies the language to use for content that can be
      rendered in different languages.

      Events:

      The following describes input events to the media primitive
      object.  The MSML Dialog Group Package allows an event exchange
      mechanism between primitives.

      pause: causes the play to enter the suspend state.

      resume: causes play to enter the generate state.




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      forward: skips forward through the media.  Only has effect when
      all child media elements are <audio>.

      backward: skips backward through the media.  Only has effect when
      all child media elements are <audio>.

      restart: skips to the beginning of the media.  Only has effect
      when all child media elements are <audio>.

      toggle-state: causes the suspend / generate state to toggle.

      terminate: terminates the play and assigns values to the shadow
      variables.

   Shadow Variables:

      play.amt: identifies the length of time for which media was
      generated before the play was stopped.  This does not include time
      that may have elapsed while the play was in the suspend state.

      play.end: contains the event that caused the play to stop.  When
      the play stops because all media generation has completed, end is
      assigned the value "play.complete".

   Note: Attributes barge and cleardb provide a simplified mechanism for
   controlling play operations with implicit DTMF without the use of
   <group> and event exchange mechanism.  When using the <play> element
   within the group framework and barge is specified, detection of barge
   condition generates an implicit terminate event to the play
   primitive.

   The following sections describe the child elements of <play>.

9.7.1.1.  <audio>

   The <audio> element identifies prerecorded audio to play.  Local URI
   references may resolve to a single physical audio clip, a logical
   clip, or a provisioned sequence of clips (physical or logical).  A
   logical clip is one that can be rendered differently based on the
   language attribute.  Logical clips are provisioned for each of the
   languages that a media server supports.  Remote URI references are
   resolved according to the capabilities of the remote server.

   Attributes:

      uri: identifies the location of the audio to be played.  The file
      and http schemes are supported.  Mandatory.




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      format: defines the encoding and file type of the audio resource.
      The format attribute is defined as a string type of form
      "audio/<filetype>;codecs=<codec>".  The keyword 'audio' identifies
      an audio content.  The codecs field identifies the audio file's
      codec to be used for decoding the audio content.  If format
      attribute is not specified, the filetype MUST be determined from
      the URI and the codec information MUST be determined from the
      media resource.

      audiosamplerate: identifies audio sample rate in kHz.  If not
      specified, the sample rate SHOULD be determined from the media
      resource.

      audiosamplesize: identifies audio sample size in bits.  If not
      specified, the sample size SHOULD be determined from the media
      resource.

      iterate: specifies the number of times the audio is to be played.
      Defaults to once '1'.

      xml:lang: specifies the language to use when the URI identifies a
      logical clip, either directly, or as part of a sequence.

9.7.1.2.  <video>

   The <video> element identifies prerecorded multimedia to play.
   Contents identified by the URI attribute may contain audio only,
   video only, or both audio and video.  The media server SHOULD attempt
   to play both audio and video from the identified URI, if both are
   available in the content.

   Attributes:

      uri: identifies the location of the video or multimedia to be
      played.  The file and http schemes are supported.  Mandatory.

      format: defines the encoding and file type of the video or
      multimedia resource.  The format attribute is defined as a string
      type of form "video/<filetype>;codecs=<codecx>,<codecy>".  The
      keyword 'video' identifies video-only media or media containing
      audio and video.  The "codecs" field identifies the audio and/or
      video codecs to be used for decoding the file content, where the
      order of the codec values is not significant.  In the event of
      audio and video content, using 'video' keyword, the
      codecs=<codecx>,<codecy> field MAY be used to identify the audio
      codec and the video codec.  If not specified, the codec
      information SHOULD be determined from the media file.




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      audiosamplerate: identifies audio sample rate in kHz.  If not
      specified, the sample rate SHOULD be determined from the media
      file.

      audiosamplesize: identifies audio sample size in bits.  If not
      specified, the sample size SHOULD be determined from the media
      file.

      codecconfig: identifies an optional special instruction string for
      codec configuration.  Default is to send no special configuration
      string to the codec.

      profile: identifies a video profile name specific to the codec.
      If not specified, default video profile of the codec SHOULD be
      selected.

      level: identifies a video profile level to the codec.  Default is
      to send no profile information to the codec and allow the codec to
      select an internal default.

      imagewidth: identifies the width of video image in pixels.
      Default is to use image width information from media file.

      imageheight: identifies the height of video image in pixels.
      Default is to use image height information from media file.


























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      maxbitrate: identifies the bitrate of the video signal in kbps.
      Default is to use maximum bitrate information from the media file.

      framerate: identifies the video frame rate in frames per second.
      Default is to use frame rate information from the media file.

      iterate: specifies the number of times the media content is to be
      played.  Defaults to once '1'.

9.7.1.3.  <media>

   The <media> element identifies multimedia content for play.  All
   content of the <media> element MUST start to play concurrently.  This
   element may be used to generate a multimedia stream from two
   independent media resources, one identifying audio and the other
   identifying video.

   The <media> element MUST contain at least one child element.  Valid
   child elements of <media> are <audio> and <video>, as described
   earlier.  <media> element MUST contain at most one <audio> element or
   at most one <video> element.

9.7.1.4.  <var>

   The <var> element specifies the generation of audio from a variable
   using prerecorded audio segments.  A variable represents a semantic
   concept (such as date or number) and dynamically produces the
   appropriate speech.

   Prerecorded audio allows an application vendor or service provider to
   choose the exact voice for their audio and therefore completely
   control the "sound and feel" of the service provided to end users.
   It provides very high audio quality and allows the variables to blend
   seamlessly into the surrounding audio segments.

   Text to speech (TTS) using Speech Synthesis Markup Language (SSML)
   [n11] may also be used to render variables, but may not provide as
   good quality, or allow as complete control of the "sound and feel" or
   user experience.  TTS is normally used for reading text such as
   emails and for very large vocabularies such as stock names.  TTS
   results in a very clear difference between the variables and the
   surrounding audio segments.  (See MSML Dialog Speech Package.)

   Attributes:

      type: specifies the type of variable.  Mandatory.  Variable type
      must be one of "date", "digits", "duration", "month", "money",
      "number", "silence", "time", or "weekday".



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      subtype: specifies an optional clarification of type.  Specific
      values depend upon the type.

      value: text that should be rendered appropriate to the type and
      subtype attributes.  Mandatory.

      xml:lang: specifies the language to use when rendering the
      variable.

9.7.1.5.  <playexit>

   The <playexit> element MUST be invoked when generation of all content
   of the <play> has come to completion.  The contents of this element
   MAY be used to send events.

   Attributes:

      none

9.7.2.  <dtmfgen>

   DTMF generator originates one or more DTMF digits in sequence.

   Attributes:

      id: an optional identifier that may be referenced elsewhere for
      sending events to the dtmfgen primitive.

      digits: a string of characters from the alphabet "0-9a-d#*" that
      correspond to a sequence of DTMF tones.  Mandatory.

      level: used to define the power level for which the tones will be
      generated.  Expressed in dBm0 in a range of 0 to -96 dBm0.  Larger
      negative values express lower power levels.  Note that values
      lower than -55 dBm0 will be rejected by most receivers (TR-
      TSY-000181, ITU-T Q.24A).  Default is -6 dBm0.

      dur: the duration in milliseconds for which each tone should be
      generated.  Implementations may round the value if they only
      support discrete durations.  Default is 100 ms.

      interval: the duration in milliseconds of a silence interval
      following each generated tone.  Implementations may round the
      value if they only support discrete durations.  Default is 100 ms.

   Events:

      terminate: terminates DTMF generation and assigns values to the



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      shadow variables.

   Shadow Variables:

      dtmfgen.end: contains the event that caused DTMF generation to
      stop.

   The following sections describe the child elements of <dtmfgen>.

9.7.2.1.  <dtmfgenexit>

   The <dtmfgenexit> element MUST be invoked when the DTMF generation
   operation completes or is terminated as a result of receiving the
   terminate event.  The <dtmfgenexit> element MAY be used to send
   events when the DTMF generation has completed.

   Attributes:

      none

9.7.3.  <tonegen>

   Tone generator allows customized tone generation.  A sequence of
   varying tones with optional silence intervals can be composed using
   the <tonegen> element.  Child elements of <tonegen>, namely <tone>
   and <silence>, specify a single tone or sequence of tones.

   Attributes:

      id: an optional identifier that may be referenced elsewhere for
      sending events to the tonegen primitive.

      iterate: A numeric value specifying the total number of
      iterations.  A value of 'forever' represents infinite repetitions.
      Optional.  Default is 1.

   Events:

      terminate: terminates tone generation and assigns values to the
      shadow variables.

   Shadow Variables:

      tonegen.end: contains the event that caused tone generation to
      stop.

   The following sections describe the child elements of <tonegen>.




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9.7.3.1.  <tone>

   The <tone> element specifies a single tone with an optional silence
   interval.  The tone specification consists of two tone frequencies,
   their attenuation values, a duration of the tone, and the number of
   times to repeat the tone.

   Attributes:

      duration: time duration or length of the individual tone,
      specified in "ms" or "s" in increments of 10 ms.  A value of 0
      represents an infinite duration.  Mandatory.

      iterate: specifies the number of times to execute the contents of
      <tone> element.  A value of 'forever' represents infinite
      repetitions.  Optional.  Default is 1.

   Events:

      none

   Child Elements:

      The child elements of <tone> element specify a single tone and an
      optional silence interval to be inserted at the end of tone
      generation.  A tone is defined by <tone1> and <tone2> elements.
      Each <tone> element MUST contain at least one of <tone1> or
      <tone2>, or MAY contain <tone1> and <tone2> exactly once.

      <tone1>

         Attributes:

            freq: specifies the frequency of the first tone in "Hz",
            ranging from 0 to 3999 Hz.  Mandatory.

            atten: specifies the attenuation level expressed in dBm0,
            ranging from 0 to -96 dBm0.  Mandatory.

      <tone2>

         Attributes:

            freq: specifies the frequency of the second tone in "Hz",
            ranging from 0 to 3999 Hz.  Mandatory.

            atten: specifies the attenuation level expressed in dBm0,
            ranging from 0 to -96 dBm0.  Mandatory.



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      <silence> - Refer to the silence element definition below.

9.7.3.2.  <silence>

   The <silence> element inserts a silence interval as optional content
   of <tonegen> or <tone> elements.

   Attributes:

      duration: specifies the amount of silence interval in "ms" or "s",
      in increments of 10ms.  Mandatory.

   Events:

      none

9.7.3.3.  <tonegenexit>

   The <tonegenexit> element MUST be invoked when the tone generation
   operation completes or is terminated as a result of receiving the
   terminate event.  The <tonegenexit> element MAY be used to send
   events when the tone generation has completed.

   Attributes:

      none

9.7.4.  <record>

   Record creates a recording.  Similar to play, <record> supports two
   states: create and suspend.  Received media becomes part of the
   recording when <record> is in the create state and is discarded when
   it is in the suspend state.

   Recording MUST be terminated when a terminate event is received or
   when a nospeech event is received and no audio has yet been recorded.
   <record> differentiates different types of terminate events.

   An optional <play> element MAY be specified as a child element of
   <record>.  This mechanism provides a complete play-record operation,
   where the prompts specified within the <play> element are played in
   advance of start of recording.

   Note: Attributes prespeech, postspeech, and termkey provide a
   simplified mechanism for controlling record operations using implicit
   DTMF and VAD, without the use of <group> and event exchange
   mechanism.




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   Attributes:

      id: an optional identifier that may be referenced elsewhere for
      sending events to the record primitive.

      append: a boolean that defines whether the recording is allowed to
      be appended to an existing file if dest already exists.  Default
      is "false".  The attribute is ignored if the scheme is http.

      dest: the destination for the recording, which will contain either
      audio only, video only, or both audio and video depending on the
      stream(s) being recorded.  Recording MAY be either local or
      external based upon the attribute value.  File and http schemes
      are supported.

      audiodest: the destination for the audio-only recording.
      Recording MAY be either local or external based upon the attribute
      value.  All combinations of dest, audiodest, and videodest are
      valid.  File and http schemes are supported.

      videodest: the destination for the video-only recording.
      Recording MAY be either local or external based upon the attribute
      value.  All combinations of dest, audiodest, and videodest are
      valid.  File and http schemes are supported.

      format: defines the encoding and file type of the recording.  The
      format attribute is defined as a string type of form
      "audio|video/filetype;codecs=x,y".  The keyword 'audio' identifies
      an audio only recording, while the keyword 'video' identifies
      video-only recording or an audio plus video recording.  The codecs
      field identifies the audio and/or video codecs to be used for the
      recording, where the order of the codec values is not significant.
      In the event of audio and video recording, using 'video' keyword,
      the codecs=x,y field MAY be used to identify the audio codec and
      the video codec.  Mandatory.

      codecconfig: identifies an optional special instruction string for
      codec configuration.  Default is to send no special configuration
      string to the codec.

      audiosamplerate: identifies audio sample rate in kHz.  If not
      specified, the sample rate SHOULD be determined from the media
      source.

      audiosamplesize: identifies audio sample size in bits.  If not
      specified, the sample size SHOULD be determined from the media
      source.




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      profile: identifies a video profile name specific to the codec.
      If not specified, default video profile of the codec SHOULD be
      selected for the recording.

      level: identifies a video profile level to the codec.  Default is
      to send no profile information to the codec and allow the codec to
      select an internal default.

      imagewidth: identifies the width of video image in pixels.
      Default is to use image width information from the media source.

      imageheight: identifies the height of video image in pixels.
      Default is to use image height information from the media source.

      maxbitrate: identifies the bitrate of the video signal in kbps.
      Default is to use maximum bitrate information from the media
      source.

      framerate: identifies the video frame rate in frames per second.
      Default is to use frame rate information from the media source.

      initial: defines the initial state for the record element.
      Default is "create", which starts the recording as soon as the
      <record> element is executed.  The "initial" attribute is
      applicable only when <record> is used within the <group>
      structure.

      maxtime: defines the maximum length of the recording in units of
      time.  Mandatory.

      prespeech: defines a timer value, in seconds, for detection of
      absence of audio energy at the start of the record operation.  If
      no audio energy is detection for the amount of time specified by
      prespeech, the recording is terminated.  Default is 0 s, which
      does not activate the prespeech timer.

      postspeech: defines a timer value, in seconds, for detection of
      absence of audio energy while the recoding is in progress.  During
      an in progress recording, if absence of audio energy is detected
      as specified by the postspeech timer, the recording is terminated.
      Default is 0 s, which disables the ability to terminate a
      recording due to postspeech silence.

      termkey: defines a single DTMF key that, when detected, terminates
      the recording.  Absence of this attribute prevents the recording
      from being terminated due to detection of DTMF digits.  When
      termkey is specified, the detected DTMF digit terminates the
      recording and the DTMF digit is not entered in the digit buffer.



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   Events:

      The following describes input events to the media primitive
      object.  The MSML Dialog Group Package allows an event exchange
      mechanism between primitives.

      pause: causes the record to enter the suspend state.  Received
      media is discarded.

      resume: causes the record to resume if it was suspended.  It has
      no effect otherwise.

      toggle-state: causes the suspend / create state to toggle.

      terminate: terminates the recording and assigns values to the
      shadow variables.

      terminate.cancelled: terminates the recording and assigns values
      to the shadow variables.  If the dest attribute used the file
      scheme, the local recording is deleted.  Applications are
      responsible for removing external files created using the http
      scheme.

      terminate.finalsilence: terminates the recording and assigns
      values to the shadow variables.  If the dest attribute used the
      file scheme, the final silence is removed from the recording.

      nospeech: terminates the recording and assigns values to the
      shadow variables if it is received and no recording has yet been
      created.  The "nospeech" event is ignored if audio has already
      been recorded.

   Shadow Variables:

      record.len: the actual length of the recording measured in units
      of time.  This does not include time that may have elapsed while
      the record was in the suspend state.

      record.end: contains the event that caused the record to
      terminate.  When the record terminates because maxtime is
      exceeded, end is assigned the value "record.complete.maxlength".

      record.recordid: contains the value of the "dest" attribute, if
      supplied, otherwise contains a media server assigned record
      identifier.

      Record termination due to prespeech silence results in assigned
      value of "record.failed.prespeech"



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      Record termination due to postspeech silence results in assigned
      value of "record.complete.postspeech"

      Record termination due to DTMF detection results in assigned value
      of "record.complete.termkey"

   The following sections describe the child elements of <record>.

9.7.4.1.  <play>

   The optional <play> element as a child element of <record> allows a
   prompt to be played prior to start of recording.  The record
   operation starts at the end of the play sequence or if the play is
   barged by DTMF, assuming that barge=true is specified for <play>.
   For a complete description, refer to <play> element.

9.7.4.2.  <tonegen>

   The optional <tonegen> element as a child element of <record> allows
   a tone or sequence of tones to be played prior to start of recording.
   The record operation starts at the end of the tone generation.  For a
   complete description, refer to <tonegen> element.

9.7.4.3.  <recordexit>

   The <recordexit> element MUST be invoked when the record operation
   completes or when the recording is terminated as a result of
   receiving the terminate event.  The <recordexit> element MAY be used
   to send events when the recording has completed.

   Attributes:

      none

9.7.5.  <dtmf> or <collect>

   DTMF input fulfills several roles within MSML dialogs.  It is used to
   trigger events that will affect the media processing operation of
   other primitives.  It is also used to collect DTMF digits from a
   media stream that are to be reported back to the user of MSML dialog.
   Often DTMF detection is used for both purposes.  Barge is the most
   common example, where a prompt is stopped based upon DTMF input but
   more digits may remain to be collected.

   DTMF detection supports multiple simultaneous recognition patterns.
   Different patterns can be used to trigger sending different events in
   order to implement DTMF controls.  Alternatively, one pattern may be




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   used to represent a collection and another pattern, a substring of
   the first, used as a barge indication.

   An optional <play> element MAY be specified as a child element of
   <dtmf> or <collect>.  This mechanism provides a complete play-collect
   operation, where the prompt(s) specified within the <play> element
   are played in advance of DTMF digit collection.

   Note that all patterns share the same digit collection buffer, inter-
   digit timing, a single <nomatch> element, and a single <noinput>
   element.  As such, multiple patterns may not be suitable to support
   simultaneous collections for different purposes.  When this is
   required, separate <dtmf> elements should be used instead.

   <dtmf> terminates if any of the <pattern>, <noinput>, or <nomatch>
   elements are matched the maximum number of times that they are
   allowed.  The number of times they may match may be specified as an
   attribute of <dtmf> or of the individual child elements.

   Element identifier <dtmf> is equivalent to <collect>.  However,
   <collect> is the preferred name.  MSML clients SHOULD use <collect>,
   while MSML servers SHOULD support both.

   Attributes:

      id: an optional identifier that may be referenced elsewhere for
      sending events to this primitive.

      cleardb: a boolean indication of whether the buffer for digit
      collection should be cleared of any collected digits when the
      element is instantiated.  If set to false, any digits currently in
      the buffer MUST be immediately compared against the pattern
      elements.

      fdt: defines the first-digit timer value.  The first-digit timer
      is started when DTMF detection is initially invoked.  If no DTMF
      digits are detected during this initial interval, the <noinput>
      element MUST be invoked.  Optional, default is 0 s (wait forever
      for the first digit).

      idt: defines the inter-digit timer to be used when digits are
      being collected.  When specified, the timer is started when the
      first digit is detected and restarted on each subsequent digit.
      Timer expiration is applied to all patterns.  After that, if any
      patterns remain active and a nomatch element is specified, the
      nomatch is executed and DTMF input MUST terminate.  The idt
      attribute should only be used when digit collection is being
      performed.  Optional, default is 4 s.



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      edt: defines the extra-digit timer value.  Specifies the length of
      time the media server MUST wait after a match to detect a
      termination key, if one is specified by the <pattern> element.
      Optional, default is 4 s.

      starttimer: boolean value that defines whether the first digit
      timer (fdt) is started initially.  When set to false, the
      starttimer event must be received for it to start.  Default is
      "false".

      iterate: specifies the number of times the <pattern>, <noinput>,
      and <nomatch> elements may be executed unless those elements
      specify differently.  The value "forever" MAY be used to indicate
      that these may be executed any number of times.  Default is once
      '1'.

      ldd: defines the minimum duration for a digit to be held in order
      for it to be detected as a long DTMF digit.  A long DTMF digit
      event MUST be treated as a single DTMF event, and MUST contain an
      extra character 'L' at the end to be distinguished from the other
      regular digit events.  For example, "#L" and "#" are different
      DTMF events.  Optional, default of 0 s.  A value of 0 s disables
      long DTMF digit detection and reporting.  Attribute value is an
      integer with a valid range from 100 ms to 100 s (units MUST be
      supplied).

   Events:

      The following describes input events to the media primitive
      object.  The MSML Dialog Group Package allows an event exchange
      mechanism between primitives.

      starttimer: starts the first digit timer (fdt) if it has not
      already been started.  Has no effect otherwise.

      terminate: terminates the DTMF input and assigns values to the
      shadow variables.

   Shadow Variables:

      dtmf.digits: the string of DTMF digits that have been received
      (the contents of the digit buffer).

      dtmf.len: the number of digits in the digit buffer.

      dtmf.last: the last digit in the digit buffer.





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      dtmf.end: contains the event that caused the <dtmf> to terminate
      or is assigned one of "dtmf.match", "dtmf.noinput", or
      "dtmf.nomatch" depending upon which of the corresponding elements
      reached its maximum.

   The following sections describe the child elements of <dtmf> or
   <collect>.

9.7.5.1.  <play>

   The optional <play> element as a child element of <dtmf> or <collect>
   allows a prompt to be played prior to DTMF digit collection.  DTMF
   digit collection starts at the end of the play sequence or if the
   play is barged by DTMF, assuming that barge=true is specified for
   <play>.  For a complete description, refer to <play> element.

9.7.5.2.  <pattern>

   The <pattern> element describes one or more DTMF digits that are to
   be recognized.  When the pattern is matched, the child elements MUST
   be executed.

   Attributes:

      digits: the digit pattern that should be matched.  Mandatory.

      format: an enumerated value that defines the format used to
      express the digit pattern.  The format may be "mgcp" or "megaco"
      for patterns expressed as a digit map from those specifications,
      or as one of the simple built-in formats defined within this
      specification.  Currently, a single built-in format "moml+digits"
      is defined that allows a match based on either one or more
      specific digits, or based upon a specific length specification
      with an optional return key.  "moml+digits" is the default.

      iterate: specifies the number of times the <pattern> may be
      matched.  The value "forever" may be used to indicate that
      <pattern> may be matched any number of times.  This value
      overrides any specified in <dtmf>.  Default is once '1'.

9.7.5.3.  <detect>

   The contents of the <detect> element MUST be executed whenever any
   DTMF is first detected.  It MUST be matched at most once.

   Attributes:

      none



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9.7.5.4.  <noinput>

   The <noinput> element is used when DTMF is being collected.  Children
   of the <noinput> element MUST be executed when DTMF has not been
   detected and the first digit timeout occurs.

   Attributes:

      iterate: specifies the number of times the <noinput> may be
      triggered.  The value "forever" may be used to indicate that
      <noinput> may be triggered any number of times.  This value
      overrides any specified in <dtmf>.  Default is once '1'.

9.7.5.5.  <nomatch>

   The <nomatch> element is used when DTMF is being collected.  Children
   of the <nomatch> element MUST be executed when it is determined that
   none of the individual patterns can be matched.

   Attributes:

      iterate: specifies the number of times the <nomatch> may be
      triggered.  The value "forever" may be used to indicate that
      <nomatch> may be triggered any number of times.  This value
      overrides any specified in <dtmf>.  Default is once '1'.

9.7.5.6.  <dtmfexit>

   The <dtmfexit> element MUST be invoked when the dtmf input completes
   because one of <pattern>, <noinput>, or <nomatch> occurred its
   maximum number of times.

   Attributes:

      None

9.7.6.  <moml>

   The root element <moml> MUST be used when the document is a stand-
   alone MSML dialog, where the invoking application media type
   indicates 'application/moml+xml'.  Additionally, for backwards
   compatibility, the <moml> element MUST be used within <dialogstart>,
   which contains an inline embedded MSML dialog.

   Valid contents of <moml> are all elements described within this MSML
   Dialog Base Package.





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   Attributes:

      version: "1.0" Mandatory.

      id: an identifier unique to this object.  Events returned from
      MSML dialog (the "target" attribute of a <send> is equal to
      "source") will be correlated with this identifier.  Mandatory.

   Events:

      terminate: terminates the MOML context.  A terminate event gets
      sent to the currently executing <group> or primitive.

9.8.  MSML Dialog Group Package

   The group package defines a single control flow construct that
   specifies concurrent execution.  Primitives are composed for
   concurrent execution by placing them within a <group> element.
   Groups define how media flows between multiple concurrently executing
   primitives.  They have one or more inputs and one or more outputs.  A
   <group> represents the declaration of a complex media processing
   operation.  The event interaction between primitives (see the
   following subsection) is defined within the context of one or more
   groups.  However groups themselves do not scope events, they simply
   define that primitives are concurrently executing and a primitive
   must be executing in order to receive an event.

   Placing primitives within a group structure is an optional feature of
   this specification.  It allows for complex services to created using
   the event exchange mechanism between the primitives.  For simpler
   services, such as play/collect or play/record, the use of group
   mechanism is not necessary.  MSML Dialog Group Package is dependent
   on the MSML Dialog Base Package.

   Groups may also be used to describe media objects that transform a
   media stream while optionally allowing application or user control of
   the transformation.  For example, a gain control could be defined
   that responds to user speech or DTMF input.  In this case, a
   recognition primitive would send events to a gain control primitive.

   Groups have one attribute that defines the media flow within them.
   They also have a dimension that defines how many media inputs and
   outputs they have.  Currently, dimensions of 1 and 2 are supported
   based upon the group topology.  These correspond to a group with one
   input and one output and a group with two inputs and two outputs.






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   Media flow to and from the primitives within the group is based upon
   a topology attribute of the <group> element.  The topology attribute
   defines a topology schema and implies the group dimension.

   There are several common ways in which primitives are often connected
   together.  A schema provides a convenient template that can be
   applied to multiple primitives without having to define all of the
   individual media relationships.  The following two schemas are
   initially defined for one-dimensional groups:

   o  parallel: specifies that media sent to the group is sent to every
      primitive that has an input.  The group bridges the output from
      every primitive that has an output into a single common group
      output.

   o  serial: specifies that the first primitive listed in the group
      receives the media sent to the group.  Its output is to be
      connected to the input of the next primitive defined within the
      group and so on until the last primitive within the group becomes
      the group output.

   Groups with these topologies are shown in the two diagrams below.
   The group on the left has a parallel topology and that on the right
   has a serial topology.

           /-> P1 --\
          /          \
   G(in) +---> P2 ----> G(out)     G(in) --> P1 --> P2 --> P3 --> G(out)
          \          /
           \-> P3 --/

   More complex media flows MAY be created by nesting groups of serial
   and parallel topologies within each other.  For example, the diagram
   below has a group with a serial topology nested within a star
   topology.

               /-----> P1 ------------------------\
              /                                    \
      Gs(in) +-> Gp(in) --> P2 --> P3 --> Gp(out) -+> Gs(out)

   This combination could be used to create record operation where DTMF
   was to be clamped from the recording itself, but a DTMF key press is
   still used to stop the recording.  In this case, P1 would be a DTMF
   recognizer, P2 would be a clamp primitive, and P3 a recorder as shown
   by the following example.  This example omits child elements and
   attributes not concerned with the core concept.  The following
   section discusses sending events, and the details of each of the
   primitives are found in section 4.



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      <group topology="parallel">
         <dtmf/>
         <group topology="serial">
            <clamp/>
            <record/>
         </group>
      </group>

   A single schema, "fullduplex", is defined for a two-dimensional
   group.  A full-duplex two-dimensional group has exactly two immediate
   children.  Those children may be primitives or other one-dimensional
   groups.  A "fullduplex" group must only be used as the top-most group
   and must not be nested.  Each primitive (P1) and group (G2) becomes
   half of the full-duplex group as shown in the diagram below.

      G-A(in1)  +-> G2 --> G-B(out1)

      G-A(out2) <-- P1 <-+ G-B(in2)

   Full-duplex groups are symmetrical when both halves are the same.
   They are asymmetrical when they differ.  Asymmetric groups need to
   have a name associated with each side.  The left side is defined as
   the input of the first child of the full-duplex group combined with
   the output of the second child.  The right side is reverse.  These
   sides were labeled A and B respectively in the preceding diagram.

   An example of a full-duplex group is the user operated gain control
   mentioned at the beginning of this subsection.  The gain should
   operate on the audio that a user hears, but the gain is controlled by
   recognizing things such as DTMF or spoken commands in media that the
   user originates.  The following shows the XML tag grouping that would
   accomplish this and corresponds to the media flow shown in the
   diagram above.  If the user's audio is not required for anything
   other than control of the gain, then the <relay> is not required and
   the internal group could be omitted.  A complete XML description for
   this is included in the examples section.

      <group topology="fullduplex">
         <group topology="parallel">
            <dtmf/>
            <relay/>
         </group>
         <gain/>
      </group>

   Primitives within a group MUST begin concurrently but MAY finish
   asynchronously based upon events that they receive or their task
   completes.  A group MUST terminate when all of the primitives within



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   it have completed.  If the group contains a <groupexit> element, then
   the contents of that element MUST be executed as part of group
   termination.

   A group itself MAY receive a terminate event requesting termination.
   A terminate event sent to the group causes a terminate event to be
   sent to each of its currently active primitives.  The <groupexit>
   element is not executed until all primitives have processed their
   respective terminate events.

9.8.1.  <group>

   The <group> element allows the contained primitives to be executed
   concurrently.

   Attributes:

      topology: specifies a schema that defines the flow of media within
      the group.  Three schemas are initially defined.  "fullduplex" is
      specified for use with two-dimensional groups.  "parallel" and
      "serial" are for use with one-dimensional groups.  The definitions
      of these topologies are in section 9.8.  Mandatory.

      id: identifies the name of the group.  Mandatory when groups are
      nested.

   Events:

      terminate: causes a terminate event to be sent to each element
      contained within the group.

9.8.2.  <groupexit>

   The <groupexit> element allows events to be sent when group
   processing completes.  Group processing completes when all contained
   primitives terminate.

   Attributes:

      none

   Events:

      none







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9.9.  MSML Dialog Transform Package

   The MSML Dialog Transform Package gathers together the simple
   primitives that work as filters on half-duplex media streams.

9.9.1.  <vad>

   Voice activity detection (VAD) is used to detect voice and silence
   when speech recognition is not required.  Similar to both speech and
   DTMF, a VAD has different media conditions that it can match.  Those
   conditions can be qualified by a minimum length of time that is
   required for them to be considered recognized.

   Attributes:

      id: an optional identifier that may be referenced elsewhere for
      sending events to the vad primitive.

      starttimer: boolean value that defines whether the timer is
      started to allow recognition of the initial condition (voice,
      silence).  When set to false, the starttimer event must be
      received in order for the initial condition to be recognized.  The
      timer does not affect recognition of the transition conditions.
      Default is "false".

   Events:

      starttimer: starts the timer to allow recognition of the initial
      condition if it has not already been started.  Has no effect
      otherwise.

      terminate: terminates voice activity detection.

   Shadow Variables:

      none

   The following sections describe the child elements of <vad>.

9.9.1.1.  <voice>, <silence>, <tvoice>, <tsilence>

   Each child element corresponds to a condition that a VAD can detect.
   The first two detect when voice or silence has been initially present
   for a minimum length of time since the VAD was started.  The second
   two require that a transition to the voice or silence condition first
   occur.





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   Attributes:

      len: the length of time the condition must persist in order to be
      recognized.  Mandatory.  In the case of <tvoice> and <tsilence>,
      the length of time applies only to the final recognized condition.

      sen: the maximum length of time the condition not being detected
      may occur without causing the detector to begin measuring that
      condition.

9.9.2.  <gain>

   Gain MAY be used to adjust of the gain of a media stream by a
   specific amount.  Application of <gain> removes any previous
   connection AGC setting used by the <agc> element.

   Attributes:

      id: an optional identifier that may be referenced elsewhere for
      sending events to the gain primitive.

      incr: an increment, expressed in dB, that will be used to adjust
      the gain when "louder" and "softer" events are received.  Default
      is 3 dB.

      amt: a specific gain to apply specified in dB.  Mandatory.

   Events:

      mute: self-explanatory.

      unmute: self-explanatory.

      reset: sets the gain to zero dB.

      louder: makes the audio on a stream louder.

      softer: makes the audio on a stream quieter.

      amt: sets the gain to the specified value between -96 dB and 96
      dB.

9.9.3.  <agc>

   Automatic gain control MAY be used to have a media server
   automatically adjust the gain of a media stream.  Application of
   <agc> removes any previous connection gain setting used by the <gain>
   element.



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   Attributes:

      id: an optional identifier that may be referenced elsewhere for
      sending events to the gain primitive.

      tgtlvl: the desired target level for AGC, specified in dBm0 with a
      valid range of -40 to 0.  Mandatory.

      maxgain: an optional attribute used to specify the maximum gain
      that AGC will apply, specified in dBm0 with a valid range of 0 to
      40, with a default of 10.

   Events:

      mute: self-explanatory.

      unmute: self-explanatory.

9.9.4.  <gate>

   The <gate> element is a simple filter that will pass or halt media,
   regardless of the format of the media stream, based on the events it
   receives.  <gate> shares the same mute and unmute events for
   compatibility with the gain primitives <gain> and <agc>.

   Attributes:

      id: an optional identifier that may be referenced elsewhere for
      sending events to the gate primitive.

      initial: the values "pass" and "halt" define whether media is
      initially allowed to pass.  Default is to pass.

   Events:

      mute: halts media flow through the primitive.

      unmute: allows media to pass through the primitive.

9.9.5.  <clamp>

   This element MAY be used to filter DTMF tones from a media stream.
   Media other than DTMF tones is passed unchanged.

   Attributes:

      id: an optional identifier that may be referenced elsewhere for
      sending events to the clamp primitive.



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   Events:

      none.

9.9.6.  <relay>

   This element is a simple primitive that copies its input to its
   output.

   Attributes:

      id: an optional identifier that may be referenced elsewhere for
      sending events to the relay primitive.

   Events:

      none.

9.10.  MSML Dialog Speech Package

   The MSML speech package defines functionality that MAY be used for
   automatic speech recognition <speech> and extends the <play>
   primitive defined in the MSML Dialog Base Package to include speech
   synthesis.  As such, this package depends on the MSML Dialog Base
   Package.

9.10.1.  <speech>

   The <speech> element activates grammars or user input rules
   associated with speech recognition.  If multiple grammars are
   specified, all are activated.  All active grammars share the same
   timers, recognition attributes, and <noinput> and <nomatch> elements.
   Each grammar may have its own <match> element.

   <speech> terminates if any of the <grammar>, <noinput>, or <nomatch>
   elements are matched the maximum number of times that they are
   allowed.  The number of times they may match may be specified as an
   attribute of <speech> or of the individual child elements.

   Attributes:

      id: an optional identifier that may be referenced elsewhere for
      sending events to the speech primitive.

      noint: specifies a time period during which speech input must be
      started; otherwise, the associated <noinput> element is invoked.





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      norect: specifies a maximum time period during which speech must
      begin to be matched; otherwise, the associated <nomatch> element
      is invoked.

      spcmplt: specifies the length of silence necessary after speech
      before a result will be finalized in the case where there is a
      complete match of an active grammar.  Following the silence, the
      appropriate <match> element will be triggered if the result is
      above the confidence level.  Otherwise, a <nomatch> element will
      be triggered.

      spincmplt: specifies the length of silence necessary after speech
      before a result will be finalized in the case where there is a
      incomplete match of all active grammars.  Following the silence,
      the <nomatch> element will be triggered.

      confidence: the minimum confidence level that the recognizer must
      have to consider a recognition result as matching a grammar.
      Expressed as an integer between 1-100.

      sens: specifies the sensitivity of the recognizer to determine
      whether speech is present.  Lower sensitivity may be required for
      the recognizer to work well in the presence of high background
      noise or line echo.

      starttimer: boolean value that defines whether the no input
      (noint) and no recognition (norect) are started initially.  When
      set to false, the starttimer event must be received in order to
      start them.  Default is "false".

      iterate: specifies the number of times the <grammar>, <noinput>,
      and <nomatch> elements may be executed unless those elements
      specify differently.  The value "forever" may be used to indicate
      that these may be executed any number of times.  Default is once
      '1'.

   Events:

      sens: sets the sensitivity of the recognizer as described above.

      starttimer: starts the no input (noint) and no recognition
      (norect) timers if they have not already been started.  Has no
      effect otherwise.

      terminate: terminates the speech input and assigns values to the
      shadow variables.





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   Shadow Variables:

      speech.end: contains the event that caused the <speech> to
      terminate or is assigned one of "speech.match", "speech.noinput",
      or "speech.nomatch" depending upon which of the corresponding
      elements reached its maximum.

      speech.results: contains the results of a matched grammar.  The
      results are formatted using the Natural Language Semantics Markup
      Language (NLSML) [n4].  When this variable is referenced to return
      results, the results are returned as a separate MIME entity.

   The following sections describe the child elements of <speech>.

9.10.1.1.  <grammar>

   The <grammar> element specifies and activates a speech grammar based
   on Speech Recognition Grammar Specification (SRGS) [n3] XML notation.
   Grammars may be referenced by a URI or defined inline.  Child
   elements of <match> MUST be executed when the specified speech
   grammar is matched.

   Attributes:

      uri: specifies the location of an SRGS grammar when the grammar is
      not defined inline.

      iterate: specifies the number of times the <grammar> may be
      matched.  The value "forever" MAY be used to indicate that
      <grammar> may be matched any number of times.  This value
      overrides any specified in <speech>.  Default is once '1'.

9.10.1.2.  <match>

   <match> is a child of <grammar> and specifies the actions to take
   when the corresponding grammar is matched.

9.10.1.3.  <noinput>

   The <noinput> element is used when speech is being recognized.
   Children of the <noinput> element MUST be executed when speech has
   not been detected and the no input timeout (noint) occurs.









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   Attributes:

      iterate: specifies the number of times the <noinput> may be
      triggered.  The value "forever" may be used to indicate that
      <noinput> may be triggered any number of times.  This value
      overrides any specified in <speech>.  Default is once '1'.

9.10.1.4.  <nomatch>

      The <nomatch> element is used when speech is being recognized.
      Children of the <nomatch> element MUST be executed when it is
      determined that none of the active grammars will match.

      Attributes:

      iterate: specifies the maximum number of times the <nomatch> may
      be triggered.  The value "forever" MAY be used to indicate that
      <nomatch> may be triggered any number of times.  This value
      overrides any specified in <speech>.  Default is once '1'.

9.10.1.5.  <speechexit>

   The <speechexit> element MUST be invoked when the speech input
   completes because one of <grammar>, <noinput>, or <nomatch> occurred
   its maximum number of times.

   Attributes:

      none

9.10.2.  <play>

   The <play> element, as defined in the MSML Dialog Base Package, is
   extended with a new child element for synthesizing speech.  From an
   XML perspective, <tts> is a member of a media substitution group.
   See the schema at the end of this document for details.

   The following sections describe the child elements of <play>.

9.10.2.1.  <tts>

   Contents of the <tts> element are rendered using text-to-speech
   services and must be compliant to the SSML specification [n11].
   Element content MAY be plain text, contain the SSML <speak> element,
   or the uri attribute should identify the location of text to be
   rendered.





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   Attributes:

      uri: identifies the location of the text to be rendered.  The file
      and http schemes are supported.

      iterate: specifies the number of times the text-to-speech block is
      to be rendered.  Defaults to once '1'.

      xml:lang: specifies the language to use when it is not explicitly
      specified as an attribute for <speak>.

9.11.  MSML Dialog Fax Detection Package

   The Fax Detection Package defines primitives that allow a media
   server to provide facsimile detection services.

9.11.1.  <faxdetect>

   Fax tone detection is used to detect the presence of the T.30 Calling
   Tone (CNG) or Called Station Identification (CED) tone in a media
   stream.  Child elements of <faxdetectexit> MUST be executed when a
   CNG tone is detected.

   Attributes:

      id: an optional identifier that may be referenced elsewhere for
      sending events to the faxdetect primitive.

   Events:

      terminate: terminates fax tone detection and assigns values to the
      associated shadow variables.

   Shadow Variables:

      faxdetect.tone: A string that specifies the fax tone type detected
      by the media server.  Values supported SHOULD include "CED",
      "CNG", or empty string.  The empty string MUST be used if fax tone
      detection terminated before detection of a fax tone, resulting in
      execution of the <faxdetectexit> element.

      faxdetect.end: A string value that specifies the reason for
      termination of <faxdetect>.  Values supported SHOULD include
      "faxdetect.complete" (due to detection of CED or CNG tone),
      "faxdetect.failed.noresource" (failed due to lack of resources on
      the media server), "faxdetect.failed" (failed due to any other
      reason) "faxdetect.terminated" (terminated by <dialogend>), or
      undefined.



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9.11.2.  <faxdetectexit>

   The <faxdetectexit> element MUST be invoked when fax detection,
   invoked via <faxdetect>, terminates.  Child elements of
   <faxdetectexit>, <send> and <exit>, allow events to be reported by
   the media server.

   Attributes:

      none

9.12.  MSML Dialog Fax Send/Receive Package

9.12.1.  <faxsend>

   The <faxsend> primitive provides the functionality of a calling fax
   terminal.  This typically means sending a set of pages.  However, it
   can also mean requesting the called terminal to send pages instead
   of, or in addition to, receiving pages.  The fax images to send are
   defined by the <sendobj> elements, described below.

   Requesting the called terminal to send pages happens when the
   <rxpoll> element is included as part of <faxsend>.  This element may
   be included in addition to, or instead of, the <sendobj> element.
   One <sendobj> (at a minimum) or <rxpoll> element must be present.
   When both are present, a media server will first send pages and will
   then poll the other terminal, requesting pages.

   Because fax is a distinct media type, the <faxsend> primitive is not
   expected to interact with other primitives.  Rather, it will interact
   using fax protocols with a remote fax terminal (or gateway) and will
   send requested status events to its invoking environment.  During fax
   operation, shadow variables are used to record the progress and
   parameters of the varying stages of fax operation.

   Status events are requested by including one or more status request
   elements.  These elements correspond to different stages or events in
   fax operation and cause predefined events to be sent to the invoking
   environment when they occur.  Since the only recipient of these
   events is expected to be a fax control agent, requests are simplified
   by associating a predefined namelist of shadow variables with each
   event.  This decision may be revisited to allowed tailored namelists
   based on further implementation experience.  Status requests apply
   both to sending and polling operation.

   Attributes:

      lclid: the identifier that a media server uses to identify itself.



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      minspeed: the minimum acceptable speed to negotiate for the
      operation.

      maxspeed: the maximum speed to negotiate for the operation.  This
      attribute is primarily for testing purposes.

      ecm: specifies whether Error Correction Mode (ECM) is allowed to
      be used if supported by the remote terminal.  Defaults to "true".

   Events:

      terminate: terminates the fax send operation.

   Shadow Variables:

      fax.rmtid: the identifier of the remote fax terminal.

      fax.rate: the negotiated speed for the operation.

      fax.resolution: identifies the resolution of the image.  Both
      metric- and inch-based resolutions are defined.  Metric-based
      resolutions are 75x75, 150x150, 204x98, 204x196, 204x391, and
      408x391.  Inch-based resolutions are 200x200, 300x300, 400x400,
      and 600x600.

      fax.pagesize: identifies the negotiated page size.  Metric sizes
      are "A3", "A4", "A5", "A6", and "B4".  Inch-based page sizes are
      "Letter" and "Legal".

      fax.encoding: identifies the image encoding utilized.  Valid
      values are "MH", "R", "MMR", and "JPEG".

      fax.ecm: identifies whether ECM operation was used.

      fax.pagebadlines: the number of bad lines in a page.

      fax.objbadlines: the number of bad lines in an object.

      fax.opbadlines: the number of bad lines in an operation.

      fax.objuri: the objuri of the current object.

      fax.resendcount: the number of pages resent due to errors.

      fax.totalpages: the number of pages processed or stored.

      fax.totalobjects: the count of the objects used in the operation.




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      fax.duration: the duration of the operation expressed as a
      duration in seconds and milliseconds (e.g., "23s250ms").

      fax.result: contains the reason that caused the fax operation to
      complete.  When the operation completes successfully, the value
      will be assigned "fax.success".  Other values include
      "fax.partial", "fax.nofax", "fax.remotedisconnect",
      "fax.uri.access.error", and "fax.invalid.startpage".

   The following sections describe the child elements of <faxsend>.

9.12.1.1.  <sendobj>

   <sendobj> is used to define a fax transmission.  There MAY be
   multiple instances of the element, which will be transmitted in
   order.

   Attributes:

      objuri: a URI that points to the fax image that will be
      transmitted.  Mandatory.

      startpage: the first page of a multi-page objuri to send.

      pagecount: page count.

9.12.1.2.  <hdrfooter>

   <hdrfooter> describes the header/footer that a media server MAY put
   on pages.  The header or footer may be defined as the content of the
   <format> child element.  The <format> element is only allowed if the
   type attribute has a value of "header" or "footer".

   Attributes:

      type: specifies whether a header or a footer should be put on
      pages and identifies the source of the header or footer.  The
      following enumerated values may be used:

         "header" indicates that the media server should put a header on
                  pages using the contents of the <format> element.

         "nohdr"  indicates that there should be no header or footer.

         "footer" indicates that the media server should put a footer on
                  pages using the contents of the <format> element.





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      style: defines the style of insertion onto a fax page that a media
      server should use for the header or footer.  Valid styles are
      "append", "overlay", or "replace".

   <format> is a child of the <hdrfooter> element that defines the style
   format to be used for the header or footer.  It uses a "C" language
   style format statement (as shown below) to define the contents and
   layout of the header or footer.

      code    length   name              format
       %a       3     day of week       3-character abbreviation
       %d       2     date              01-31
       %m       2     month             01-12
       %y       2     year              00-99
       %Y       4     year              0000-9999
       %I       2     12 hour           01-12
       %H       2     24 hour           00-23
       %M       2     minute            00-59
       %S       2     seconds           00-59
       %p       2     AM/PM             AM or PM
       %P       2     page number       01-99
       %T       2     total pages       01-99
       %l       20    local ID (sender) 0-9, + or spaces
       %r       20    remote ID (rcvr)  0-9, + or spaces
       %%       1     percent           display % in header/ftr

9.12.1.3.  <rxpoll>

   <rxpoll> provides the information necessary for a receive polling
   operation to occur.  The object(s) to be received are defined by one
   or more <rcvobj> elements.  The <rcvobj> is defined further under the
   child elements of <faxrcv>.  The <rxpoll> element MAY also include a
   description of the header/footer that a media server SHOULD put on
   received pages.  The <hdrfooter> element and its usage is described
   above.

   Attributes:

      rmtid: specifies the identifier of the remote fax terminal that is
      to be associated with a polling operation.  A media server MUST
      NOT execute a polling operation unless the value of rmtid matches
      that of the connected remote machine.  Mandatory.









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9.12.1.4.  <faxstart>

   The <faxstart> element requests that an event be sent when fax
   operation has begun.  When triggered, the following will be executed:

   <send target="source" event="fax.start"/>

9.12.1.5.  <faxnegotiate>

   The <faxnegotiate> element requests that an event be sent when a
   negotiation has been completed.  Multiple events MAY be sent each
   time a Digital Command Signal (DCS) frame is sent or received.  When
   triggered, the following will be executed:

      <send target="source" event="fax.negotiate"
         namelist="fax.rmtid
            fax.rate
            fax.resolution
            fax.pagesize
            fax.encoding
            fax.ecm"/>

9.12.1.6.  <faxpagedone>

   The <faxpagedone> element requests that an event be sent when a page
   has been sent or received.  When triggered, the following will be
   executed:

      <send target="source" event="fax.pagedone"
            namelist="fax.resolution
            fax.pagesize
            fax.encoding
            fax.pagebadlines
            fax.resendcount"/>

9.12.1.7.  <faxobjectdone>

   The <faxobjectdone> element requests that an event be sent when an
   objuri has been completed.  When triggered, the following will be
   executed:

      <send target="source" event="fax.objectdone"
            namelist="fax.objuri
            fax.objbadlines
            fax.resendcount
            fax.totalpages
            fax.result"/>




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9.12.1.8.  <faxopcomplete>

   The <faxopcomplete> element requests that an event be sent when an
   operation has been completed.  When triggered, the following will be
   executed:

      <send target="source" event="fax.opcomplete"
            namelist="fax.totalpages
            fax.opbadlines
            fax.resendcount
            fax.totalobjects
            fax.duration
            fax.result"/>

9.12.1.9.  <faxpollstarted>

   The <faxpollstarted> element requests that an event be sent when a
   polling operation has started.  When triggered, the following will be
   executed:

      <send target="source" event="fax.opcomplete"
            namelist="fax.rmtid
            fax.rate
            fax.resolution
            fax.pagesize
            fax.encoding
            fax.ecm"/>

9.12.2.  <faxrcv>

   The <faxrcv> primitive provides the functionality of a called fax
   terminal.  Typically this type of operation is to receive pages.
   However, it can include sending pages instead of, or in addition to,
   receiving them.  The fax objects to receive are defined by the
   <rcvobj> elements, described below.

   A media server SHOULD send pages as a polled terminal when the
   <txpoll> element is included as part of <faxrcv>.  This element may
   be included in addition to, or instead of, the <rcvobj> element.  One
   <rcvobj> or <txpoll> element must be present.  When both are present,
   a media server SHOULD first receive pages and will then allow the
   other terminal to poll the media server, requesting pages.

   Because fax is a distinct media type, the <faxrcv> primitive is not
   expected to interact with other primitives.  Rather, it will interact
   using fax protocols with a remote fax terminal and will send





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   requested status events to its invoking environment.  During fax
   operation, shadow variables are used to record the progress and
   parameters of the varying stages of fax operation.

   Status events are requested by including one or more status request
   elements.  These elements correspond to different stages or events in
   fax operation and cause predefined events to be sent to the invoking
   environment when they occur.  Since the only recipient of these
   events is expected to be a fax control agent, requests are simplified
   by associating a predefined namelist of shadow variables with each
   event.  This decision may be revisited to allowed tailored namelists
   based on further implementation experience.  Status requests apply
   both to receiving and polling operation.

   Attributes:

      id: an optional identifier that may be referenced elsewhere for
      sending events to the faxrecv primitive.

      lclid: the identifier that a media server uses to identify itself.

      ecm: specifies whether ECM mode is allowed to be used if supported
      by the remote terminal.  Defaults to "true".

   Events:

      terminate: terminates the fax reception operation.

   Shadow Variables:

      <faxrcv> supports the same set of shadow variables as <faxsend>

      The following sections describe the child elements of <faxrcv>.

      In addition to the elements defined below, <faxrcv> MAY also have
      the following child elements, which were defined under <faxsend>:

      o  <hdrfooter>
      o  <faxstart>
      o  <faxnegotiate>
      o  <faxpagedone>
      o  <faxobjectdone>
      o  <faxopcomplete>
      o  <faxpollstarted>

   Their meaning and usage are the same as previously defined.





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9.12.2.1.  <rcvobj>

   <rcvobj> is used to define fax objects that a media server will
   receive.  There may be multiple instances of the element, which will
   be used in order.

   Attributes:

      objuri: a URI that points to the location that a received image is
      to be stored.  Mandatory.

      maxpages: the maximum number of pages that will be stored in
      objuri.

9.12.2.2.  <txpoll>

   <txpoll> provides the information for a polling operation to occur as
   part of a fax receive operation.  An object or multiple objects to be
   sent may be supplied by one or more <sendobj> elements.  In the event
   of multiple occurrences, a media server MUST select the <sendobj>
   element whose rmtid attribute matches that of the remote terminal.

   The <sendobj> element was defined previously as a child element of
   <faxsend>.  The <txpoll> element is extended with an rmtid attribute
   that specifies the identifier of the remote fax terminal and is used
   to select the specific <sendobj> to send.

   A media server SHOULD put a header/footer on transmitted pages based
   on any <hdrfooter> element included as part of <txpoll>.

   Attributes:

      rmtid: specifies the identifier of the remote fax terminal that is
      to be associated with a polling operation.  A media server MUST
      NOT execute a polling operation unless the value of rmtid matches
      that of the connected remote machine.  Mandatory.

10.  MSML Audit Package

10.1.  MSML Audit Core Package

   This section describes the MSML Audit Core Package that MAY be
   implemented to support auditing services.

   Audit requests and results may vary based on the information being
   audited.  The MSML Audit Core Package specifies the framework to send
   audit request, defines a state list, and builds audit results.  The




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   additional audit packages define package specific state lists and
   associated audit result content.  The additional audit packages MUST
   be defined within the framework specified by the Audit Core Package.

10.1.1.  <audit>

   The <audit> element is an optional child element of <msml>, which MAY
   be used by MSML clients to perform state auditing of current media
   resources allocated and in use by the media server.  The requested
   state information is returned in an MSML response.

   Attributes:

      queryid: the identifier of the MSML object being queried by the
      MSML client.  Mandatory.  Supported object types: conference or
      connection.  Wildcards are allowed.

      statelist: a list of one or more state parameters that are being
      queried.  Optional.  If not present, the media server SHOULD
      return the id of audited object only.  Each object type may
      contain a set of states.  If the "statelist" contains any state
      that does not match the audited object type, the request MUST be
      rejected.

      mark: in the case of an error, the value of the mark attribute
      from the last successfully executed element that included the mark
      attribute.

   State Parameters:

      The state parameter MUST be named using a dot-notation format
      "audit.X.a.b.c...", where X is the mandatory field that indicates
      the class name of the object (e.g., "conf" or "conn") and the
      "a.b.c..."  is the optional field used to describe the actual name
      of the state parameter in a hierarchical manner.  The wildcard "*"
      MAY be used as part of a state name; however, it MUST only be used
      in the last field of the dot-notation (e.g., "audit.conf.*" is
      valid, but "audit.conf.*.a" is invalid).  When a wildcard is used,
      it is equivalent to querying all the states below the specified
      level.  Each field (e.g., within "a.b.c...") will result in
      individual element names <a>, <b>, and <c> in the audit result to
      contain corresponding state value.  The parent/child relationship
      between these elements follows the hierarchy of the state name
      (i.e., <c> is child element of <b>, and <b> is child element of
      <a>).






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10.1.2.  <auditresult>

   The <auditresult> element is an optional child element of <result>,
   which MUST be used by the media server to return the audit result.  A
   specific instance of the <auditresult> element contains the state
   information of a single active object.  Therefore, if multiple
   objects are within the scope of the audit request, then one
   <auditresult> element per object MUST be present.  A zero occurrence
   of <auditresult> element indicates that there are no active resources
   within the scope of the audit request.

   Attributes:

      targetid: the identifier of a conference or connection.
      Mandatory.  Wildcard is not allowed.

   The <auditresult> may contain child element(s) that return additional
   state information, corresponding to the "statelist" attribute in the
   <audit> request.  The child element names correspond to the fields of
   the state parameter name (e.g., "a.b.c..."), following the same
   hierarchical structure.

10.2.  MSML Audit Conference Package

   This section describes the MSML Audit Conference Package that MUST be
   implemented to support auditing of conference services.  The MSML
   Audit Conference Package follows the framework specified by the MSML
   Audit Core Package.  This package defines the state parameter list
   and audit result for conference auditing.

10.2.1.  State Parameters

   All conference state parameter names MUST be prefixed by
   "audit.conf".

      confconfig: query the conferences general configuration.

      confconfig.audiomix: query the audio mixer's general configuration
      in the conference.

      confconfig.audiomix.asn: query the current ASN setting in the
      audio mixer.

      confconfig.audiomix.n-loudest: query the current n-loudest setting
      in the audio mixer.

      confconfig.videolayout: query the video layout's general
      configuration in the conference.



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      confconfig.videolayout.root: query the root window setting of the
      video layout.

      confconfig.videolayout.selector: query the video stream selector
      setting of the video layout.

      confconfig.controller: query who is the conference controller.

      dialog: query the active dialog information on the conference.
      See MSML Audit Dialog Package for details.

      stream: query the active stream information on the conference.
      See MSML Audit Stream Package for details.

10.2.2.  <auditresult>

   The <auditresult> attribute of "targetid" is required to indicate
   results for auditing a conference.

   The <auditresult> element may optionally contain the following child
   elements, returning additional conference state information, if
   corresponding states are queried and available.

10.2.2.1.  confconfig

   The <confconfig> element is used to return the general configuration
   state(s) of a conference, using the following attributes.

   Attributes:

      deletewhen: as defined by <createconference> element in MSML
      Conference Core Package.

      term: as defined by <createconference> element in MSML Conference
      Core Package.

10.2.2.2.  confconfig.audiomix

   The <audiomix> element contains the general audio mixer configuration
   using the following attributes.

   Attributes:

      id: as defined by <audiomix> element in MSML Conference Core
      Package.

      samplerate: as defined by <audiomix> element in MSML Conference
      Core Package.



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10.2.2.3.  confconfig.audiomix.asn

   The <asn> element contains the current ASN setting of an audio mixer,
   if ASN is enabled.  The state values are included in the following
   attributes.

   Attributes:

      ri: as defined by <asn> element in MSML Conference Core Package.

      asth: as defined by <asn> element in MSML Conference Core Package.

10.2.2.4.  confconfig.audiomix.n-loudest

   The <n-loudest> element contains the current n-loudest setting of the
   audio mixer.  The state values are included in the following
   attributes.

   Attributes:

      n: as defined by <n-loudest> element in MSML Conference Core
      Package.

10.2.2.5.  confconfig.videolayout

   The <videolayout> element contains the general video layout
   configuration using the following attributes.

   Attributes:

      id: as defined by <videolayout> in MSML Conference Core Package.

      type: as defined by <videolayout> in MSML Conference Core Package.

10.2.2.6.  confconfig.videolayout.root

   The <root> element is used to contain root window settings.

   Attributes:

      size: as defined by <root> element in MSML Conference Core
      Package.

      backgroundcolor: as defined by <root> element in MSML Conference
      Core Package.

      Backgroundimage: as defined by <root> element in MSML Conference
      Core Package.



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10.2.2.7.  confconfig.videolayout.selector

   The <selector> element is used to contain selector settings.

   Attributes:

      id: as defined by <selector> element in MSML Conference Core
      Package.

      method: as defined by <selector> element in MSML Conference Core
      Package.

      status: as defined by <selector> element in MSML Conference Core
      Package.

      blankothers: as defined by <selector> element in MSML Conference
      Core Package.

      si: as defined by <selector> element in MSML Conference Core
      Package when selector method is "vas".

      speakersees: as defined by <selector> element in MSML Conference
      Core Package when selector method is "vas".

10.2.2.8.  confconfig.controller

   The <controller> element is used to return the conference controller
   id in its content.  The conference controller is the SIP dialog that
   carries the <createconference> request.  The return value is the MSML
   connection id.

10.2.2.9.  dialog

   If conference dialog state is queried, the audit result is returned
   using the <dialog> element as specified in the MSML Audit Dialog
   Package.

10.2.2.10.  stream

   If conference stream state is queried, the audit result is returned
   using the <stream> element as specified in the MSML Audit Stream
   Package.









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10.3.  MSML Audit Connection Package

   This section describes the MSML Audit Connection Package that MAY be
   implemented to support auditing connection services.  The MSML Audit
   Connection Package follows the framework specified by the MSML Audit
   Core Package.  This package defines the state parameter list and
   audit result for connection auditing.

10.3.1.  State Parameters

   Connection state parameter names are prefixed by "audit.conn".

      sipdialog: queries the identifier of the SIP dialog with which the
      connection is associated.

      sipdialog.localseq: queries one of the SIP dialog states - local
      sequence number.

      sipdialog.remoteseq: queries one of the SIP dialog states - remote
      sequence number.

      sipdialog.localURI: queries one of the SIP dialog states - local
      URI.

      sipdialog.remoteURI: queries one of the SIP dialog states - remote
      URI.

      sipdialog.remotetarget: queries one of the SIP dialog states -
      remote target.

      sipdialog.routeset: queries one of the SIP dialog states - route
      set.

      localsdp: queries the local SDP body of the connection.

      remotesdp: queries the remote SDP body of the connection.

      dialog: queries the active dialog information on the connection.
      See MSML Audit Dialog Package for details.

      stream: queries the active stream information on the connection.
      See MSML Audit Stream Package for details.

10.3.2.  <auditresult>

   The <auditresult> attribute "targetid" MUST specify a connection
   identifier for a connection result.




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   The <auditresult> element MAY contain the following child elements
   optionally to return additional connection state information if the
   corresponding states are queried and are available.

10.3.2.1.  sipdialog

   The <sipdialog> element contains the associated SIP dialog
   information.  The SIP dialog ID information is returned using the
   following attributes.

      Attributes:

         callid: call-ID value as defined in [n1].  Mandatory.

         localtag: local-tag value as defined in [n1].  Mandatory.

         remotetag: remote-tag value as defined in [n1].  Mandatory.

   This element can contain the following child elements optionally to
   return additional SIP dialog state information to the client if the
   corresponding states are queried and available.

10.3.2.2.  sipdialog.localseq

   The <localseq> element contains the local sequence number.  The local
   sequence number is one of the SIP dialog states as defined in [n1].

10.3.2.3.  sipdialog.remoteseq

   The <remoteseq> element contains the remote sequence number.  The
   remote sequence number is one of the SIP dialog states as defined in
   [n1].

10.3.2.4.  sipdialog.localuri

   The <localuri> element contains the local URI value.  The local URI
   is one of the SIP dialog states as defined in [n1].

10.3.2.5.  sipdialog.remoteuri

   The <remoteuri> element contains the remote URI value.  The remote
   URI is one of the SIP dialog states as defined in [n1].

10.3.2.6.  sipdialog.remotetarget

   The <remotetarget> element contains the remote target value.  The
   remote target is one of the SIP dialog states as defined in [n1].




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10.3.2.7.  sipdialog.routeset

   The <routeset> element contains the route-set value (an ordered list
   of URIs separated by comma).  The route set is one of the SIP dialog
   states as defined in [n1].

10.3.2.8.  localsdp

   The <localsdp> element contains the local SDP body.

10.3.2.9.  remotesdp

   The <remotesdp> element contains the remote SDP body.

10.3.2.10.  dialog

   If the connection dialog state is queried, the audit result returns
   the queried information using the <dialog> element, as specified in
   the MSML Audit Dialog Package.

10.3.2.11.  stream

   If the connection stream state is queried, the audit result returns
   the queried information using the <stream> element, as specified in
   the MSML Audit Stream Package.

10.4.  MSML Audit Dialog Package

   This section describes the MSML Audit Dialog Package that MAY be
   implemented to support auditing dialogs.  The MSML Audit Dialog
   Package follows the framework specified by the MSML Audit Core
   Package.

   The MSML Audit Dialog Package must be used together with either the
   MSML Audit Conference Package or MSML Audit Connection Package, since
   the dialogs are applicable to conferences or connections.

10.4.1.  State Parameters

   Dialog state parameter names are prefixed by "dialog".  Since this
   package must be used together with the MSML Audit Conference Package
   or MSML Audit Connection Package, the complete dialog state name must
   be prefixed by "audit.conf.dialog" or "audit.conn.dialog", depending
   on the context within which the dialog state is queried.

   dialog: queries the number of active dialog(s) running on the target
   (a conference or connection); basic dialog information will be
   returned.



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   dialog.duration: queries the amount of time a dialog has been
   running.

   dialog.primitive: queries the media primitive currently being
   executed by the dialog.

   dialog.controller: queries the dialog controller.

10.4.2.  <dialog>

   The <dialog> element is a child element of <auditresult>, which
   contains the active dialog information on the target identified by
   the attribute "targetid" of the <audioresult> element.

   Basic dialog information is returned using the following attributes.

   Attributes:

      src: as defined by the <dialogstart> element in the MSML Dialog
      Core Package.

      type: as defined by the <dialogstart> element in the MSML Dialog
      Core Package.  Mandatory.

      name: as defined by the <dialogstart> element in the MSML Dialog
      Core Package.  Mandatory.

   This element may contain the following child elements optionally to
   return additional dialog information if the corresponding state
   parameter has been queried and the state value is available.

10.4.2.1.  <duration>

   The <duration> element returns the duration that a dialog has been
   running on the specified target.  The duration value is included in
   the element content.  It is a positive integer value (in unit of
   seconds).

10.4.2.2.  <primitive>

   The <primitive> element returns the currently active media primitive
   in its content.  The active media primitive is the primitive that is
   currently being executed.  Possible return values are play, dtmf,
   collect, dtmfgen, tonegen, record, or none.







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10.4.2.3.  <controller>

   The <controller> element returns the dialog controller id in its
   content.  The dialog controller is the SIP dialog that carries the
   <dialogstart> request.  The returned value is the MSML connection id.

10.5.  MSML Audit Stream Package

   This section describes the MSML Audit Stream Package that MAY be
   implemented to support auditing stream.  The MSML Audit Stream
   Package follows the framework specified by the MSML Audit Core
   Package.

   The MSML Audit Stream Package MUST be used together with either the
   MSML Audit Conference Package or the MSML Audit Connection Package,
   since the stream is applicable between conferences, between
   connections, or between conferences and connections.

10.5.1.  State Parameters

   Stream state parameter names are prefixed by "stream".  Since this
   package must be used together with the MSML Audit Conference Package
   or MSML Audit Connection Package, the complete stream state name must
   be prefixed by "audit.conf.stream" or "audit.conn.stream", depending
   on the context within which the stream state is queried.

   stream: queries the number of active streams created on the audited
   object; basic stream information will be returned.

   stream.clamp: queries the clamping status.

   stream.gain: queries the gain control information.

   stream.visual: queries the visual setting.

10.5.2.  <stream>

   The <stream> element is a child element of <auditresult> and contains
   the active stream information on the target identified by the
   attribute "targetid" of the <audioresult> element.

   Basic stream information is returned using the following attributes.

   Attributes:

      joinwith: an identifier of either a connection or a conference
      with which the audited object is joined.  Mandatory.  Wildcard is
      not allowed.



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      media: as defined by the <stream> element in the MSML Conference
      Core Package.  Mandatory.

      dir: direction of stream, from audited target perspective, "from"
      or "to".  Mandatory.

      compressed: as defined by the <stream> element in the MSML
      Conference Core Package.

      display: as defined by the <stream> element in the MSML Conference
      Core Package.

      override: as defined by the <stream> element in the MSML
      Conference Core Package.

      preferred: as defined by the <stream> element in the MSML
      Conference Core Package.

   This element MAY contain the following child elements that optionally
   return additional stream information, if the corresponding state
   parameter is queried and the state value is available.

10.5.2.1.  <clamp>

   The <clamp> element is included if stream clamping is active.  The
   currently active clamping state values are returned using the
   attributes as defined by the <clamp> element in the MSML Conference
   Core Package.

10.5.2.2.  <gain>

   The <gain> element is included if stream gain is active.  The current
   gain control state values are returned using the attributes as
   defined by the <gain> element in the MSML Conference Core Package.

10.5.2.3.  <visual>

   The <visual> element is included if stream visual display is active.
   The current visual display settings are returned using the attributes
   as defined by the <visual> element in the MSML Conference Core
   Package.

11.  Response Codes

   Response codes are used to indicate reasons for failures as well as
   completion status.  The appropriate code and description must be
   passed to the invoking environment on failure.




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   The response codes defined in this section are returned as the value
   of the response attribute to the <result> element.  Some values may
   also be returned as part of a namelist to an "msml.dialog.exit" event
   generated when an executing MSML dialog fails.

   Informational (1xx)

      Reserved for future use

   Success (200)

      200  OK

   Request Error (4xx)

      400  Bad Request
      401  Unknown Element
      402  Unsupported Element
      403  Missing mandatory element content
      404  Forbidden element content
      405  Invalid element content
      406  Unknown attribute
      407  Attribute not supported
      408  Missing mandatory attribute
      409  Forbidden attribute is present

      410  Invalid attribute value

      420  Unsupported media description language
      421  Unknown media description language
      422  Ambiguous request (both URI and inline description)
      423  External document fetch error
      424  Syntax error in foreign language
      425  Semantic error in foreign language
      426  Unknown error executing foreign language

      430  Object does not exist
      431  Object instance name already used
      432  Conference name already in use
      433  reserved
      434  External document fetch error

      440  Cannot join objects of the specified class
      441  Objects have incompatible media types
      442  reserved
      443  reserved
      444  Number of media inputs exceeded




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      450  Objects have incompatible media formats
      451  Incompatible media stream format

   Server Error (5xx)

      500  Internal media server error
      503  Service Unavailable
      510  Not in service
      511  Service Unavailable
      520  No resource to fulfill request
      521  Internal limit exceeded

12.  MSML Conference Examples

   These examples focus on the MSML Conference Core Package used by a
   control agent (CA) to control services on a media server (MS).  They
   show the relationship between SIP signaling to establish media
   sessions and MSML service control commands.  For brevity, only the
   content of MSML messages is shown.  The examples assumes that the CA
   and MS use the IPv4 address and UDP port number of the audio stream
   (on the MS) to identify the MSML connection.

12.1.  Establishing a Dial-In Conference

      UA                   Control Agent             Media Server
      |                         |                           |
      |                         |        INVITE F1          |
      |                         |-------------------------->|
      |                         |           200 F2          |
      |                         |<--------------------------|
      |                         |           ACK F3          |
      |                         |-------------------------->|
      |                         |                           |
      |                         |     createconference> F4  |
      |                         |-------------------------->|
      |                         |           200 F5          |
      |                         |<--------------------------|
      |    INVITE (SDP UA) F6   |                           |
      |------------------------>|                           |
      |                         |      INVITE (SDP UA) F7   |
      |                         |-------------------------->|
      |                         |        200 (SDP MS) F8    |
      |                         |<--------------------------|
      |                         |           ACK F9          |
      |                         |-------------------------->|
      |     200 (SDP MS) F10    |                           |
      |<------------------------|                           |
      |        ACK F11          |                           |



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      |------------------------>|                           |
      |                         |     <dialogstart> F12     |
      |                         |-------------------------->|
      |                         |           200 F13         |
      |                         |<--------------------------|
      |                         |    HTTP interactions F14  |
      |                         |<------------------------->|
      |                         |  <event>(dialog.exit) F15 |
      |                         |<--------------------------|
      |                         |         <join> F16        |
      |                         |-------------------------->|
      |                         |           200 F17         |
      |                         |<--------------------------|
      |         ...             |            ...            |
      |                         |                           |
      |                         |     <dialogstart> F18     |
      |                         |-------------------------->|
      |                         |           200 F19         |
      |                         |-------------------------->|
      |                         |    HTTP interactions F20  |
      |                         |<--------------------------|
      |                         |  <event>(dialog.exit) F21 |
      |                         |-------------------------->|
      |         ...             |            ...            |
      |                         |                           |

   Steps 1-3: establish an MSML control channel for the conference.
   Alternatively, a control channel could already have been established
   that was used for all CA/MS interactions.  A control channel per
   conference is only one possible model.  Currently, MSML uses SIP INFO
   requests and responses on this SIP dialog.  There is a proposal to
   use this message exchange to establish a TCP channel for MSML similar
   to the approach used for the Media Resource Control Protocol v2
   (MRCPv2).  This approach would require that a request identifier be
   added to the <msml> element to correlate requests and responses.
   This currently relies on the SIP INFO request and response for this
   property.  MSML messages are shown without specifying the transport
   in this example, but it assumes a request/response correlation based
   on transport messages.

   Step 4: create a conference that will mix the loudest two speakers
   and report those speakers to the control agent every 10 seconds.  The
   media server will automatically terminate remaining media sessions
   and delete the conference and associated resources and when the
   control channel is terminated.






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      <msml version="1.1">
         <createconference name="exampleConf" deletewhen="nocontrol">
             <audiomix>
                <n-loudest n="3"/>
                <asn ri="10s"/>
             </audiomix>
         </createconference>
      </msml>

   Step 5: conference created successfully

      <msml version="1.1">
         <result response="200"/>
      </msml>

   Steps 6-11: standard 3PCC establishment of a user-initiated media
   session to a media server.  This is the equivalent of a dial-in
   conference participant.  The "To:" header returned by the MS in the
   200 response of Step F8 was:

   To: <sip:msml@ms.example.com>;tag=jd87dfg4h

   Step 12: request an initial dialog with the participant to prompt for
   their name, desired conference, etc.  The dialog completes by
   informing the participant that they are joining the conference.  If
   this was not the first participant, the dialog could also announce
   the other participants.

      <msml version="1.1">
         <dialogstart target="conn:jd87dfg4h" name="12345"
             type="application/vxml+xml"
             src="http://server.example.com/scripts/initial.vxml"/>
      </msml>

   Step 13: dialog started successfully.  The dialog identifier is
   returned.

      <msml version="1.1">
         <result response="200"/>
         <dialogid>conn:jd87dfg4h/dialog:12345</dialogid>
      </msml>

   Step 14: sequence of HTTP VoiceXML dialog interactions.

   Step 15: the VoiceXML browser exits (but does not disconnect).  If a
   namelist had been specified within the VoiceXML <exit> element, it
   would have been included in the <event> sent to the CA.




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      <msml version="1.1">
         <event name="msml.dialog.exit"
                id="conn:jd87dfg4h/dialog:12345"/>
      </msml>

   Step 16: join the participant to the conference and have the volume
   of their contributing audio automatically adjusted to a target level
   of -20 dBm0.

      <msml version="1.1">
         <join id1="conn:jd87dfg4h" id2="conf:exampleConf">
            <stream media="audio" dir="from-id1">
                <gain agc="true" tgtlvl="-20"/>
            </stream>
            <stream media="audio" dir="to-id1"/>
      </msml>

   Step 17: successfully joined to conference

      <msml version="1.1">
         <result response="200"/>
      </msml>

   Steps 6 through 17 are repeated for the second participant.

   Step 18: play a join tone or message announcing the new participant
   to the conference.

      <msml version="1.1">
         <dialogstart target="conf:exampleConf"
             type="application/vxml+xml"
             src="http://server.example.com/scripts/joinmsg.vxml"/>
      </msml>

   Step 19: dialog started successfully.  The dialog identifier is
   returned.  The media server assigned a unique identifier since name
   attribute was not specified in <dialogstart>.

      <msml version="1.1">
         <result response="200"/>
         <dialogid>conf:ExampleConf/dialog:j6fs8745</dialogid>
      </msml>

   Step 20: HTTP VoiceXML dialog interaction(s).







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   Step 21: the VoiceXML browser exits.

      <msml version="1.1">
         <event name="msml.dialog.exit"
                id="conf:ExampleConf/dialog:j6fs8745"/>
      </msml>

   Steps 6 through 21 are repeated for the third and subsequent
   participants.

12.2.  Example of a Sidebar Audio Conference

   This example assumes that a conference has already been established
   as in the previous example.  It creates a sidebar conference that
   hears the main conference as a whisper.  Three participants are moved
   to the sidebar.  After some period of time, the sidebar participants
   are returned to the main conference and the sidebar is deleted.

   Step 1: the sidebar conference is created.  It is joined half-duplex
   to the main conference and a manual gain object is inserted in the
   media stream.  Three participants are then moved from the main
   conference to the sidebar.  Although not shown, a CA could include
   the "mark" attribute in each element to allow recovery in the event
   of a mid- transaction error.

      <msml version="1.1">
         <createconference name="sidebarConf"
                           deletewhen="nomedia">
             <audiomix/>
         </createconference>
         <join id1="conf:sidebarConf" id2="conf:exampleConf">
             <stream media="audio" dir="to-id1">
                 <gain amt="-20"/>
             </stream>
         </join>
         <unjoin id1="conn:gs5s4-1" id2="conf:exampleConf"/>
         <join id1="conn:gs5s4-1" id2="conf:sidebarConf"/>
         <unjoin id1="conn:hd764gr9-2" id2="conf:exampleConf"/>
         <join id1="conn:hd764gr9-2" id2="conf:sidebarConf"/>
         <unjoin id1="conn:h37frdvgs65-3" id2="conf:exampleConf"/>
         <join id1="conn:h37frdvgs65-3" id2="conf:sidebarConf"/>
      </msml>









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   Step 2: sidebar conference created successfully and participants
   joined.

      <msml version="1.1">
         <result response="200"/>
      </msml>

   Step 3: once the sidebar conference has completed, the participants
   are rejoined to the main conference.  The sidebar is destroyed
   automatically by the MS when the last media stream is removed as
   specified when the sidebar conference was created.

      <msml version="1.1">
         <unjoin id1="conn:gs5s4-1" id2="conf:sidebarConf"/>
         <join id1="conn:gs5s4-1" id2="conf:exampleConf"/>
         <unjoin id1="conn:hd764gr9-2" id2="conf:sidebarConf"/>
         <join id1="conn:hd764gr9-2" id2="conf:exampleConf"/>
         <unjoin id1="conn:h37frdvgs65-3" id2="conf:sidebarConf"/>
         <join id1="conn:h37frdvgs65-3" id2="conf:exampleConf"/>
      </msml>

   Step 4: participants successfully moved to main conference and
   sidebar destroyed.

      <msml version="1.1">
         <result response="200"/>
      </msml>

12.3.  Example of Removing a Conference

   This example assumes a conference created similar to the first
   example where there is an MSML control channel specific to the
   conference and the conference has been configured to be deleted when
   that channel is removed (using SIP).

   Steps 1-2: the CA signals BYE for the SIP dialog used to establish
   the conference control channel.

   Steps 3-6: the MS initiates terminating the media sessions for each
   participant remaining in the conference.

   The MS deletes the conference and removes all resources when the last
   participant has been removed.

12.4.  Example of Modifying Video Layout

   Assume that a conference named "example" is created using the
   following mixer descriptions.



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      +---+---+
      | 1 | 2 |
      +---+---+
      | 3 | 4 |
      +---+---+

      <createconference name="quad-split">
         <audiomix>
            <n-loudest n="3"/>
            <asn ri="10s"/>
         </audiomix>
         <videolayout>
            <root size="CIF" background="white" />
            <selector id="default" method="vas" si="500ms">
               <region id="1" left="0" top="0" relativesize="1/4"/>
            </selector>
            <region id="2" left="50%" top="0" relativesize="1/4"/>
            <region id="3" left="0%" top="50%" relativesize="1/4">
            <region id="4" left="50%" top="50%" relativesize="1/4"/>
         </videolayout>
      </createconference>

      The following would change the size of the video window to QCIF
      and the background color to the default "black".

      <modifyconference id="conf:example">
         <videolayout>
            <root size="4CIF"/>
         </videolayout>
      </modifyconference>

   The relative location of the regions does not change.  However, the
   sizes of the regions do change because they are relative to the size
   of the root window.  The result is a layout that looks identical but
   half the size.

   The following would freeze the video displayed in region "2" without
   affecting any other attributes of that region.

      <modifyconference id="conf:example">
         <videolayout>
            <region id="2" left="50%" top="0" relativesize="1/4"
                           freeze="true"/>
         </videolayout>
      </modifyconference>






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13.  MSML Dialog Examples

   These examples focus on the MSML Dialog Base Package and the MSML
   Dialog Group Package.

13.1.  Announcement

   The following is a simple announcement scenario.  Two recorded audio
   files are played in sequence followed by generated speech followed by
   a variable.  The results are reported once media generation
   completes.

      <?xml version="1.0" encoding="UTF-8"?>
      <msml version="1.1">
         <dialogstart target="conn:12345" name="12345">
            <play>
               <audio uri="file://clip1.wav"/>
               <audio uri="http://host1/clip2.wav"/>
               <tts uri="http://host2/text.ssml"/>
               <var type="date" subtype="mdy" value="20030601"/>
            </play>
            <send target="source" event="done" namelist="play.amt
                                               play.end"/>
         </dialogstart>
      </msml>

13.2.  Voice Mail Retrieval

   Below is an example that shows a simple voice mail retrieval
   operation consisting of playing a message and allowing the user to
   pause and resume play using '5' to toggle the state.  The operation
   would terminate when the play completed or the user entered '#'.

   During the play, the user can advance forward and backward through
   the message as well as rewinding to the beginning.
















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      <?xml version="1.0" encoding="UTF-8"?>
      <msml version="1.1">
        <dialogstart target="conn:12345" name="12345">
         <group topology="parallel">
            <play>
               <audio uri="file://message.wav"/>
               <playexit>
                  <send target="group" event="terminate"/>
               </playexit>
            </play>
            <dtmf iterate="forever">
               <pattern digits="5">
                  <send target="play" event="toggle-state"/>
               </pattern>
               <pattern digits="6">
                  <send target="play" event="forward"/>
               </pattern>
               <pattern digits="7">
                  <send target="play" event="backward"/>
               </pattern>
               <pattern digits="8">
                  <send target="play" event="restart"/>
               </pattern>
               <pattern digits="#">
                  <send target="play" event="terminate"/>
               </pattern>
            </dtmf>
         </group>
       </dialogstart>
      </msml>





















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13.3.  Play and Record

   A more complex example is a play and record operation.  This sources
   and sinks media and uses voice activity DTMF detection and
   recognition to influence behavior.  Any DTMF input or voice activity
   will barge the play and cause the record to begin.  However, if the
   prompt was barged with a DTMF digit of '#', the record terminates
   without starting.  When the play terminates, it send a starttimer
   event to the VAD to allow it to recognize an initial silence
   condition.  The recording will be terminated (without starting) when
   the VAD detects an initial 3 seconds of silence.

   Once resumed (based upon voice detection), the recording may be
   terminated under several conditions.  It will terminate after 5
   seconds of silence or after 60 seconds elapses.  It will also
   terminate if a '#' key is recognized.  Every aspect of this behavior
   can be modified by changing what is recognized and the events that
   are sent.  The following example uses the MSML Dialog Group Package.

































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      <?xml version="1.0" encoding="UTF-8"?>
      <msml  version="1.1">
       <dialogstart target="conn:12345" name="12345">
         <group topology="parallel">
            <play>
               <audio uri="file://prompt.wav"/>
               <playexit>
                  <send target="vad" event="starttimer"/>
               </playexit>
            </play>
            <dtmf>
               <pattern digits="#">
                  <send target="record" event="terminate.termkey"/>
               </pattern>
               <detect>
                  <send target="play" event="terminate"/>
               </detect>
            </dtmf>
            <vad>
               <voice len="10ms">
                  <send target="play" event="terminate"/>
                  <send target="record" event="resume"/>
               </voice>
               <silence len="3s">
                  <send target="record" event="nospeech"/>
               </silence>
               <tsilence len="5s">
                  <send target="record" event="terminate.finalsilence"/>
               </tsilence>
            </vad>
            <record initial="suspend" maxtime="60s"
                    dest="file://record.wav" format="g729">
               <recordexit>
                  <send target="group" event="terminate"/>
               </recordexit>
            </record>
            <groupexit>
               <send target="source" event="done"
                     namelist="record.len record.end"/>
            </groupexit>
         </group>
       </dialogstart>
      </msml>








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   The following implements the same functionality, as described above,
   in using the MSML Dialog Base Package, using the <record> composite
   mechanism for the play and record operation.

   <?xml version="1.0" encoding="UTF-8"?>
   <msml  version="1.1">
    <dialogstart target="conn:12345" name="12345">
      <record prespeech="3s" postspeech="5s" maxtime="60s" termkey="#"
                 dest="file://record.wav" format="g729">
         <play barge="true">
            <audio uri="file://prompt.wav"/>
         </play>
         <recordexit>
            <send target="source" event="done"
                  namelist="record.len record.end"/>
         </recordexit>
      </record>
    </dialogstart>
   </msml>
































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13.4.  Speech Recognition

   The following simple example requests that a user speak the name of a
   city and returns the result.

      <?xml version="1.0" encoding="UTF-8"?>
      <msml version="1.1">
       <dialogstart target="conn:12345" name="12345">
         <group topology="parallel">
            <play>
               <audio uri="file://prompt.wav"/>
            </play>
            <speech>
               <grammar version="1.0">
                  <rule id="city" scope="public">
                     <item>
                        <one-of>
                           <item>vancouver</item>
                           <item>new york</item>
                           <item>london</item>
                        </one-of>
                     </item>
                  </rule>
                  <match>
                     <send target="group" event="terminate"/>
                  </match>
               </grammar>
               <noinput>
                  <send target="group" event="terminate"/>
               </noinput>
               <nomatch>
                  <send target="group" event="terminate"/>
               </nomatch>
            </speech>
            <groupexit>
               <send target="source" event="done"
                             namelist="speech.end speech.results"/>
            </groupexit>
         </group>
       </dialogstart>
      </msml>

13.5.  Play and Collect

   This example prompts a user to enter 4 DTMF digits terminated by the
   '#' key (represented by "xxxx#" below).  The prompt will be barged
   and the user has 10 seconds to begin entering input or no input will
   be indicated.



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      <?xml version="1.0" encoding="UTF-8"?>
      <msml version="1.1">
       <dialogstart target="conn:12345" name="12345">
         <group topology="parallel">
            <play>
               <audio uri="file://prompt.wav"/>
               <playexit>
                  <send target="dtmf" event="starttimer"/>
               </playexit>
            </play>
            <dtmf fdt="10s" idt="16s">
               <pattern digits="xxxx#">
                  <send target="group" event="terminate"/>
               </pattern>
               <detect>
                  <send target="play" event="terminate"/>
               </detect>
               <noinput>
                  <send target="group" event="terminate"/>
               </noinput>
               <nomatch>
                  <send target="group" event="terminate"/>
               </nomatch>
            </dtmf>
            <groupexit>
               <send target="source" event="done"
                     namelist="dtmf.digits dtmf.end"/>
            </groupexit>
         </group>
       </dialogstart>
      </msml>




















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   The following implements the same functionality, as described above,
   using the MSML Dialog Base Package, using the <collect> composite
   mechanism for the play and collect operation.

      <?xml version="1.0" encoding="UTF-8"?>
      <msml version="1.1">
       <dialogstart target="conn:12345" name="12345">

         <collect fdt="10s" idt="16s">
            <play barge="true">
               <audio uri="file://prompt.wav"/>
            </play>
            <pattern digits="xxxx#">
               <send target="source" event="done"
                     namelist="dtmf.digits dtmf.end"/>
            </pattern>
            <noinput>
               <send target="source" event="done"
                     namelist="dtmf.end"/>
            </noinput>
            <nomatch>
               <send target="source" event="done"
                     namelist="dtmf.end"/>
            </nomatch>
         </collect>
       </dialogstart>
      </msml>
























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13.6.  User Controlled Gain

   This shows an example of nesting groups to create an arbitrary full-
   duplex media control.  DTMF is detected on media flowing in one
   direction and used to adjust the gain applied to media flowing in the
   opposite direction.  Additionally, the stream that is used to detect
   DTMF has DTMF removed and its gain automatically adjusted before
   leaving the group.  This widget could be used between a conference
   participant and a conference mixer.

      <?xml version="1.0" encoding="UTF-8"?>
      <msml  version="1.0">
       <dialogstart target="conn:12345" name="12345">
         <group topology="fullduplex">
            <group topology="parallel">
               <dtmf>
                  <pattern digits="1" iterate="forever">
                     <send target="gain" event="louder"/>
                  </pattern>
                  <pattern digits="2" iterate="forever">
                     <send target="gain" event="softer"/>
                  </pattern>
               </dtmf>
               <group topology="serial">
                  <clamp/>
                  <agc tgtlvl="0"/>
               </group>
            </group>
            <gain amt="0" incr="5"/>
         </group>
       </dialogstart>
      </msml>

14.  MSML Audit Examples

   The following examples describe the MSML Audit Conference Package and
   the MSML Audit Connection Package, and their use together with the
   MSML Audit Dialog Package or/and the MSML Audit Stream Package.

14.1.  Audit All Conferences

   This example describes an audit of all active conferences on the
   media server, querying the conference configurations.

      <?xml version="1.0" encoding="UTF-8"?>
      <msml version="1.1">
         <audit queryid="conf:*" statelist="audit.conf.confconfig.*"/>
      </msml>



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   The following result assumes two conferences currently allocated by
   the media server.  Conference "conf:1" contains both an audio mixer
   (with ASN enabled) and a video layout (vas) created, while conference
   "conf:2" contains only an audio mixer created with ASN disabled.

      <?xml version="1.0" encoding="UTF-8"?>
      <msml version="1.1">
         <result response="200">
            <auditresult targetid="conf:1">
               <confconfig deletewhen="nocontrol" term="true">
                  <audiomix id="audiomix1">
                     <asn ri="5s"/>
                     <n-loudest n="16"/>
                  </audiomix>
                    <videolayout id="videolayout1"
                                 type="text/msml-basic-layout">
                       <selector id="selector1" method="vas" si="5s"
                                 speakersees="current">
                          <root size="CIF"/>
                       </selector>
                    </videolayout>
                  <controller>conn:1234</controller>
               </confconfig>
            </auditresult>
            <auditresult targetid="conf:2">
               <confconfig deletewhen="nomedia" term="true">
                  <audiomix id="audiomix2">
                     <n-loudest n="1"/>
                  </audiomix>
                  <controller>conn:1234</controller>
               </confconfig>
            </auditresult>
         </result>
      </msml>

14.2.  Audit Conference Dialogs

   This example describes an audit of active dialogs on a specific
   conference.  The request queries all available dialog states.

      <?xml version="1.0" encoding="UTF-8"?>
      <msml version="1.1">
         <audit queryid="conf:1" statelist="audit.conf.dialog.*"/>
      </msml>

   The example result assumes a single dialog running on conference
   "conf:1", which has been running for 60 seconds, and the dialog is
   currently executing a record operation.



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      <?xml version="1.0" encoding="UTF-8"?>
      <msml version="1.1">
         <result response="200">
            <auditresult targetid="conf:1">
               <dialog name="sample">
                  <duration>60</duration>
                  <primitive>record</primitive>
                  <controller>conn:1234</controller>
               </dialog>
            </auditresult>
         </result>
      </msml>

14.3.  Audit Conference Streams

   This example request describes an audit of active streams on a
   specific conference.  The request queries all available stream
   states.

      <?xml version="1.0" encoding="UTF-8"?>
      <msml version="1.1">
         <audit queryid="conf:1" statelist="audit.conf.stream.*"/>
      </msml>

   The example result assumes three audio participants in the
   conference.  Connection "conn:1234" is a talk-listen participant with
   both clamp and gain control enabled.  Connection "conn:1235" is a
   talk-only participant.  Connection "conn:1236" is a listen-only
   participant with automatic gain control enabled.






















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      <?xml version="1.0" encoding="UTF-8"?>
      <msml version="1.1">
         <result response="200">
            <auditresult targetid="conf:1">
               <stream joinwith="conn:1234" media="audio" dir="to">
                  <clamp dtmf="true" tone="false"/>
                  <gain amt="-10"/>
               </stream>
               <stream joinwith="conn:1234" media="audio" dir="from">
                  <gain amt="10"/>
               </stream>
               <stream joinwith="conn:1235" media="audio" dir="to">
               </stream>
               <stream joinwith="conn:1236" media="audio" dir="from">
                  <gain agc="true" tgtlvl="0" maxgain="10"/>
               </stream>
            </auditresult>
         </result>
      </msml>

14.4.  Audit All Connections

   This example request describes an audit of all active connections on
   the media server.  No additional state is queried.

      <?xml version="1.0" encoding="UTF-8"?>
      <msml version="1.1">
         <audit queryid="conn:*"/>
      </msml>

   The example result assumes five connections currently allocated by
   the media server.

      <?xml version="1.0" encoding="UTF-8"?>
      <msml version="1.1">
         <result response="200">
            <auditresult targetid="conn:1230"/>
            <auditresult targetid="conn:1231"/>
            <auditresult targetid="conn:1232"/>
            <auditresult targetid="conn:1233"/>
            <auditresult targetid="conn:1234"/>
         </result>
      </msml>

14.5.  Audit Connection Dialogs

   This example request describes an audit of active dialogs on a
   specific connection.  No additional dialog state is queried.



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      <?xml version="1.0" encoding="UTF-8"?>
      <msml version="1.1">
         <audit queryid="conn:1234" statelist="audit.conn.dialog"/>
      </msml>

   The example result assumes three dialogs running on the connection.

      <?xml version="1.0" encoding="UTF-8"?>
      <msml version="1.1">
         <result response="200">
            <auditresult targetid="conn:1234">
               <dialog name="sample1"/>
               <dialog name="sample2"/>
               <dialog name="sample3"/>
            </auditresult>
         </result>
      </msml>

14.6.  Audit Connection Streams

   This example request describes an audit of active streams on a
   specific connection.  No additional stream state is queried.

      <?xml version="1.0" encoding="UTF-8"?>
      <msml version="1.1">
         <audit queryid="conn:1234" statelist="audit.conn.stream"/>
      </msml>

   The example result assumes three audio streams created between target
   connection and other MSML objects, one of which is a bidirectional
   stream between target connection and a conference, and two are
   unidirectional streams between two other connections.

      <?xml version="1.0" encoding="UTF-8"?>
      <msml version="1.1">
         <result response="200">
            <auditresult targetid="conn:1234">
               <stream joinwith="conf:1" media="audio" dir="to"/>
               <stream joinwith="conf:1" media="audio" dir="from"/>
               <stream joinwith="conn:1235" media="audio" dir="to"/>
               <stream joinwith="conn:1236" media="audio" dir="from"/>
            </auditresult>
         </result>
      </msml>







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14.7.  Audit Connection with Selective States

   This example describes an audit of a specific connection, querying
   associated SIP dialog ID and SDP info.

      <?xml version="1.0" encoding="UTF-8"?>
      <msml version="1.1">
         <audit queryid="conn:1234" statelist="audit.conn.sipdialog
            audit.conn.localsdp audit.conn.remotesdp"/>
      </msml>

      <?xml version="1.0" encoding="UTF-8"?>
      <msml version="1.1">
         <result response="200">
            <auditresult targetid="conn:1234">
               <sipdialog callid="ABCD@10.0.0.10:5060"
                          localtag="sdfjsiodf"
                          remotetag="zvnmviuhd8"/>
               <localsdp>
                  v=0
                  o=- 31691 31691 IN IP4 ms5mpc11.lab.radisys.com
                  s=media server session
                  t=0 0
                  m=audio 33794 RTP/AVP 0
                  c=IN IP4 10.3.5.111
                  a=rtpmap:0 PCMU/8000
                  a=sendrecv
                  m=video 32770 RTP/AVP 34
                  c=IN IP4 10.3.5.11
                  b=AS:48
                  a=rtpmap:34 H263/90000
                  a=fmtp:34 CIF=1
                  a=sendrecv
               </localsdp>
               <remotesdp>
                  v=0
                  o=- 12345 12345 IN IP4 10.0.0.88
                  s=RadiSys SIP Media Server session
                  t=0 0
                  c=IN IP4 10.0.0.126
                  b=AS:128
                  m=audio 10000 RTP/AVP 0
                  a=rtpmap:0 PCMU/8000
                  a=ptime:20
                  a=sendrecv
                  m=video 10002 RTP/AVP 34
                  a=rtpmap:34 H263/90000
                  a=fmtp:34 CIF=1



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                  a=sendrecv
               </remotesdp>
            </auditresult>
         </result>
      </msml>

15.  Future Work

   The following capabilities may be added in future versions of this
   document:

   o Ability for MSML clients to audit or query the media server for
     supported set of MSML packages and profiles.

   o Ability to version MSML packages and profiles and naming scheme for
     MSML extension packages.

16.  XML Schema

   MSML specification consists of a set of XML schemas, all of which may
   be used together or any sub-set of the schemas may be used for each
   MSML package.  The following sections define a complete set of
   schemas covering all MSML packages.

   Each package contains a single schema file, <package-name>-
   datatypes.xsd.  This schema file can be included by its extended
   package(s).  Every package optionally contains another schema file,
   <package_name>.xsd, which can be used directly to build or validate
   MSML scripts for a given package.

   The complete MSML schema (msml.xsd) includes all the individual MSML
   packages.

   <?xml version="1.0" encoding="UTF-8"?>
   <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
              elementFormDefault="qualified"
              attributeFormDefault="unqualified">
    <xs:include schemaLocation="msml-core-datatypes.xsd"/>
    <xs:include schemaLocation="msml-conf-core-datatypes.xsd"/>
    <xs:include schemaLocation="msml-dialog-core-datatypes.xsd"/>
    <xs:include schemaLocation="msml-dialog-base-datatypes.xsd"/>
    <xs:include schemaLocation="msml-dialog-transform-datatypes.xsd"/>
    <xs:include schemaLocation="msml-dialog-group-datatypes.xsd"/>
    <xs:include schemaLocation="msml-dialog-speech-datatypes.xsd"/>
    <xs:include schemaLocation="msml-dialog-fax-detect-datatypes.xsd"/>
    <xs:include schemaLocation="msml-dialog-fax-sendrecv-
                datatypes.xsd"/>
    <xs:include schemaLocation="msml-audit-core-datatypes.xsd"/>



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    <xs:include schemaLocation="msml-audit-conf-datatypes.xsd"/>
    <xs:include schemaLocation="msml-audit-conn-datatypes.xsd"/>
    <xs:include schemaLocation="msml-audit-dialog-datatypes.xsd"/>
    <xs:include schemaLocation="msml-audit-stream-datatypes.xsd"/>
    <xs:element name="msml">
     <xs:complexType>
      <xs:choice>
       <xs:group ref="msmlRequestType" maxOccurs="unbounded"/>
       <xs:element name="event">
        <xs:complexType>
         <xs:choice maxOccurs="unbounded">
          <xs:sequence>
           <xs:element name="name" type="msmlEventNameValue.datatype"/>
           <xs:element name="value">
            <xs:simpleType>
             <xs:restriction base="xs:string">
              <xs:pattern value="[a-zA-Z0-9.]+"/>
             </xs:restriction>
            </xs:simpleType>
           </xs:element>
          </xs:sequence>
         </xs:choice>
         <xs:attribute name="name" type="msmlEventName.datatype"
                       use="required"/>
         <xs:attribute name="id" type="msmlEventSource.datatype"
                       use="required"/>
        </xs:complexType>
       </xs:element>
       <xs:element name="result">
        <xs:complexType>
         <xs:choice>
          <xs:element ref="description" minOccurs="0"/>
          <xs:sequence>
           <xs:element ref="msmlResultSimple" minOccurs="0"
                       maxOccurs="unbounded"/>
           <xs:element ref="msmlResultComplex" minOccurs="0"
                       maxOccurs="unbounded"/>
          </xs:sequence>
         </xs:choice>
         <xs:attribute name="response">
          <xs:simpleType>
           <xs:restriction base="xs:string">
            <xs:pattern value="\d{3}"/>
           </xs:restriction>
          </xs:simpleType>
         </xs:attribute>
         <xs:attribute name="mark" type="mark.datatype"/>
        </xs:complexType>



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       </xs:element>
      </xs:choice>
      <xs:attribute name="version" type="xs:string" use="required"
                    fixed="1.1"/>
     </xs:complexType>
    </xs:element>
   </xs:schema>

16.1.  MSML Core

16.1.1.  msml-core.xsd

   <?xml version="1.0" encoding="UTF-8"?>
   <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
   elementFormDefault="qualified" attributeFormDefault="unqualified">
    <xs:include schemaLocation="msml-core-datatypes.xsd"/>
    <xs:element name="msml">
     <xs:complexType>
      <xs:choice>
       <xs:group ref="msmlRequestType" maxOccurs="unbounded"/>
       <xs:element name="event">
        <xs:complexType>
         <xs:choice maxOccurs="unbounded">
          <xs:sequence>
           <xs:element name="name" type="msmlEventNameValue.datatype"/>
           <xs:element name="value">
            <xs:simpleType>
             <xs:restriction base="xs:string">
              <xs:pattern value="[a-zA-Z0-9.]+"/>
             </xs:restriction>
            </xs:simpleType>
           </xs:element>
          </xs:sequence>
         </xs:choice>
         <xs:attribute name="name" type="msmlEventName.datatype"
                       use="required"/>
         <xs:attribute name="id" type="msmlEventSource.datatype"
                       use="required"/>
        </xs:complexType>
       </xs:element>
       <xs:element name="result">
        <xs:complexType>
         <xs:choice>
          <xs:element ref="description" minOccurs="0"/>
          <xs:sequence>
           <xs:element ref="msmlResultSimple" minOccurs="0"
                       maxOccurs="unbounded"/>
           <xs:element ref="msmlResultComplex" minOccurs="0"



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                       maxOccurs="unbounded"/>
          </xs:sequence>
         </xs:choice>
         <xs:attribute name="response">
          <xs:simpleType>
           <xs:restriction base="xs:string">
            <xs:pattern value="\d{3}"/>
           </xs:restriction>
          </xs:simpleType>
         </xs:attribute>
         <xs:attribute name="mark" type="mark.datatype"/>
        </xs:complexType>
       </xs:element>
      </xs:choice>
      <xs:attribute name="version" type="xs:string" use="required"
                    fixed="1.1"/>
     </xs:complexType>
    </xs:element>
   </xs:schema>

16.1.2.  msml-core-datatypes.xsd

   <?xml version="1.0" encoding="UTF-8"?>
   <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
              elementFormDefault="qualified"
              attributeFormDefault="unqualified">
    <xs:group name="msmlRequestType">
     <xs:choice>
      <xs:element ref="msmlRequest"/>
      <xs:element name="send">
       <xs:complexType>
        <xs:complexContent>
         <xs:extension base="msmlRequestType">
          <xs:attribute name="event" type="msmlEvent.datatype"
                        use="required"/>
          <xs:attribute name="target" type="msmlTarget.datatype"
                       use="required"/>
          <xs:attribute name="valuelist" type="xs:string"/>
         </xs:extension>
        </xs:complexContent>
       </xs:complexType>
      </xs:element>
     </xs:choice>
    </xs:group>
    <xs:element name="msmlRequest" type="msmlRequestType"
                abstract="true"/>
    <xs:complexType name="msmlRequestType">
     <xs:attribute ref="mark"/>



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    </xs:complexType>
    <xs:element name="msmlResultSimple" type="msmlResultSimpleType"
                abstract="true"/>
    <xs:element name="msmlResultComplex" type="msmlResultComplexType"
                abstract="true"/>
    <xs:simpleType name="msmlResultSimpleType">
     <xs:restriction base="xs:string"/>
    </xs:simpleType>
    <xs:complexType name="msmlResultComplexType"/>
    <xs:element name="description" type="xs:string"/>
    <xs:attribute name="mark" type="mark.datatype"/>
    <xs:simpleType name="msmlInstanceID.datatype">
     <xs:restriction base="xs:string">
      <xs:pattern value="[a-zA-Z0-9.:\-_]+"/>
     </xs:restriction>
    </xs:simpleType>
    <xs:simpleType name="connID.datatype">
     <xs:restriction base="xs:string">
      <xs:pattern value="conn:[a-zA-Z0-9.:\-_]+"/>
     </xs:restriction>
    </xs:simpleType>
    <xs:simpleType name="confID.datatype">
     <xs:restriction base="xs:string">
      <xs:pattern value="conf:[a-zA-Z0-9.:\-_]+"/>
     </xs:restriction>
    </xs:simpleType>
    <xs:simpleType name="dialogID.datatype">
     <xs:restriction base="xs:string">
   <xs:pattern value="conf:[a-zA-Z0-9.:\-_]+/dialog:[a-zA-Z0-9.:\-_]+"/>
   <xs:pattern value="conn:[a-zA-Z0-9.:\-_]+/dialog:[a-zA-Z0-9.:\-_]+"/>
     </xs:restriction>
    </xs:simpleType>
    <xs:simpleType name="independentID.datatype">
     <xs:restriction base="xs:string">
      <xs:pattern value="conf:[a-zA-Z0-9.:\-_]+"/>
      <xs:pattern value="conn:[a-zA-Z0-9.:\-_]+"/>
     </xs:restriction>
    </xs:simpleType>
    <xs:simpleType name="dialogLanguage.datatype">
     <xs:restriction base="xs:string">
      <xs:enumeration value="application/moml+xml"/>
      <xs:enumeration value="application/voicexml+xml"/>
     </xs:restriction>
    </xs:simpleType>
    <xs:simpleType name="msmlEvent.datatype">
     <xs:restriction base="xs:string"/>
    </xs:simpleType>
    <xs:simpleType name="msmlSend.datatype">



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     <xs:restriction base="xs:string"/>
    </xs:simpleType>
    <xs:simpleType name="msmlEventName.datatype">
     <xs:restriction base="xs:string">
      <xs:pattern value="msml.dialog.exit"/>
      <xs:pattern value="msml.conf.asn"/>
      <xs:pattern value="msml.conf.nomedia"/>
      <xs:pattern value="msml.dialog.exit"/>
      <xs:pattern value="[a-zA-Z0-9.:_\-]+"/>
     </xs:restriction>
    </xs:simpleType>
    <xs:simpleType name="msmlTarget.datatype">
     <xs:restriction base="xs:string">
      <xs:pattern
   value="conf:[a-zA-Z0-9.:_\-]+(/oper:[a-zA-Z0-9.:_\-]+|\*)*"/>
      <xs:pattern
   value="conn:[a-zA-Z0-9.:_\-]+(/oper:[a-zA-Z0-9.:_\-]+|\*)+"/>
     </xs:restriction>
    </xs:simpleType>
    <xs:simpleType name="msmlEventSource.datatype">
     <xs:restriction base="xs:string">
      <xs:pattern value="conf:[a-zA-Z0-9.:_\-]+"/>
      <xs:pattern value="(conf:[a-zA-Z0-9.:_\-]+|conn:[a-zA-Z0-9.:_\-
      ]+)/dialog:[a-zA-Z0-9.:_\-]+"/>
     </xs:restriction>
    </xs:simpleType>
    <xs:simpleType name="msmlEventNameValue.datatype">
     <xs:restriction base="xs:string"/>
    </xs:simpleType>
    <xs:simpleType name="mark.datatype">
     <xs:restriction base="xs:string">
      <xs:pattern value="[a-zA-Z0-9.:\-_]+"/>
     </xs:restriction>
    </xs:simpleType>
    <xs:simpleType name="boolean.datatype">
     <xs:restriction base="xs:string">
      <xs:enumeration value="true"/>
      <xs:enumeration value="false"/>
     </xs:restriction>
    </xs:simpleType>
    <xs:simpleType name="posDuration.datatype">
     <xs:restriction base="xs:string">
      <xs:pattern value="(\+)?([0-9]*\.)?[0-9]+(ms|s)"/>
     </xs:restriction>
    </xs:simpleType>
   </xs:schema>





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16.2.  MSML Conference Core Package

16.2.1.  msml-conf-core.xsd

   <?xml version="1.0" encoding="UTF-8"?>
   <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
              elementFormDefault="qualified"
              attributeFormDefault="unqualified">
      <xs:include schemaLocation="msml-core.xsd"/>
      <xs:include schemaLocation="msml-conf-core-datatypes.xsd"/>
   </xs:schema>

16.2.2.  msml-conf-core-datatypes.xsd

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
           elementFormDefault="qualified"
           attributeFormDefault="unqualified">
 <xs:include schemaLocation="msml-core-datatypes.xsd"/>
 <xs:element name="createconference" substitutionGroup="msmlRequest">
  <xs:complexType>
   <xs:complexContent>
    <xs:extension base="msmlRequestType">
     <xs:all>
      <xs:element name="audiomix" type="audioMixType" minOccurs="0"/>
      <xs:element name="videolayout" type="videoLayoutType"
                  minOccurs="0"/>
      <xs:element name="reserve" minOccurs="0">
       <xs:complexType>
        <xs:sequence>
         <xs:element name="resource" maxOccurs="unbounded">
          <xs:complexType>
           <xs:sequence>
            <xs:any namespace="##other" processContents="lax"
                    minOccurs="0" maxOccurs="unbounded"/>
           </xs:sequence>
           <xs:attribute name="n" type="xs:positiveInteger"
                        default="1"/>
           <xs:anyAttribute namespace="##any"/>
          </xs:complexType>
         </xs:element>
        </xs:sequence>
        <xs:attribute name="required" type="boolean.datatype"
                      default="true"/>
       </xs:complexType>
      </xs:element>
     </xs:all>
     <xs:attribute name="name" type="msmlInstanceID.datatype"/>



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     <xs:attribute name="deletewhen" default="never">
      <xs:simpleType>
       <xs:restriction base="xs:string">
        <xs:enumeration value="nomedia"/>
        <xs:enumeration value="nocontrol"/>
        <xs:enumeration value="never"/>
       </xs:restriction>
      </xs:simpleType>
     </xs:attribute>
     <xs:attribute name="term" type="boolean.datatype" default="true"/>
    </xs:extension>
   </xs:complexContent>
  </xs:complexType>
 </xs:element>
 <xs:element name="modifyconference" substitutionGroup="msmlRequest">
  <xs:complexType>
   <xs:complexContent>
    <xs:extension base="msmlRequestType">
     <xs:all>
      <xs:element name="audiomix" type="audioMixType" minOccurs="0"/>
      <xs:element name="videolayout" type="videoLayoutType"
                  minOccurs="0"/>
     </xs:all>
     <xs:attribute name="id" type="confID.datatype" use="required"/>
    </xs:extension>
   </xs:complexContent>
  </xs:complexType>
 </xs:element>
 <xs:element name="destroyconference" substitutionGroup="msmlRequest">
  <xs:complexType>
   <xs:complexContent>
    <xs:extension base="msmlRequestType">
     <xs:all>
      <xs:element name="audiomix" type="basicAudioMixType"
                  minOccurs="0"/>
      <xs:element name="videolayout" type="basicVideoLayoutType"
                  minOccurs="0"/>
     </xs:all>
     <xs:attribute name="id" type="confID.datatype" use="required"/>
    </xs:extension>
   </xs:complexContent>
  </xs:complexType>
 </xs:element>
 <xs:element name="join" substitutionGroup="msmlRequest">
  <xs:complexType>
   <xs:complexContent>
    <xs:extension base="msmlRequestType">
     <xs:sequence>



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      <xs:element name="stream" type="streamType" minOccurs="0"
                  maxOccurs="4"/>
     </xs:sequence>
     <xs:attribute name="id1" type="independentID.datatype"
                   use="required"/>
     <xs:attribute name="id2" type="independentID.datatype"
                   use="required"/>
    </xs:extension>
   </xs:complexContent>
  </xs:complexType>
 </xs:element>
 <xs:element name="modifystream" substitutionGroup="msmlRequest">
  <xs:complexType>
   <xs:complexContent>
    <xs:extension base="msmlRequestType">
     <xs:sequence>
      <xs:element name="stream" type="streamType" maxOccurs="4"/>
     </xs:sequence>
     <xs:attribute name="id1" type="independentID.datatype"
                   use="required"/>
     <xs:attribute name="id2" type="independentID.datatype"
                   use="required"/>
    </xs:extension>
   </xs:complexContent>
  </xs:complexType>
 </xs:element>
 <xs:element name="unjoin" substitutionGroup="msmlRequest">
  <xs:complexType>
   <xs:complexContent>
    <xs:extension base="msmlRequestType">
     <xs:sequence>
      <xs:element name="stream" type="basicStreamType" minOccurs="0"
                  maxOccurs="4"/>
     </xs:sequence>
     <xs:attribute name="id1" type="independentID.datatype"
                   use="required"/>
     <xs:attribute name="id2" type="independentID.datatype"
                   use="required"/>
    </xs:extension>
   </xs:complexContent>
  </xs:complexType>
 </xs:element>
 <xs:element name="monitor" substitutionGroup="msmlRequest">
  <xs:complexType>
   <xs:complexContent>
    <xs:extension base="msmlRequestType">
     <xs:attribute name="id1" type="connID.datatype" use="required"/>
     <xs:attribute name="id2" type="independentID.datatype"



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                   use="required"/>
     <xs:attribute name="compressed" type="boolean.datatype"
                   default="false"/>
    </xs:extension>
   </xs:complexContent>
  </xs:complexType>
 </xs:element>
 <xs:element name="confid" type="msmlResultSimpleType"
             substitutionGroup="msmlResultSimple"/>
 <xs:complexType name="basicStreamType">
  <xs:attribute name="dir">
   <xs:simpleType>
    <xs:restriction base="xs:string">
     <xs:enumeration value="to-id1"/>
     <xs:enumeration value="from-id1"/>
    </xs:restriction>
   </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="media">
   <xs:simpleType>
    <xs:restriction base="xs:string">
     <xs:enumeration value="audio"/>
     <xs:enumeration value="video"/>
    </xs:restriction>
   </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="compressed" type="boolean.datatype"/>
 </xs:complexType>
 <xs:complexType name="streamType">
  <xs:complexContent>
   <xs:extension base="basicStreamType">
    <xs:choice minOccurs="0" maxOccurs="unbounded">
     <xs:element name="gain">
      <xs:complexType>
       <xs:attribute name="amt" use="optional">
        <xs:simpleType>
         <xs:restriction base="xs:integer">
          <xs:minInclusive value="-96"/>
          <xs:maxInclusive value="96"/>
         </xs:restriction>
        </xs:simpleType>
       </xs:attribute>
       <xs:attribute name="agc" type="boolean.datatype"/>
       <xs:attribute name="tgtlvl" use="optional">
        <xs:simpleType>
         <xs:restriction base="xs:nonPositiveInteger">
          <xs:minInclusive value="-40"/>
          <xs:maxInclusive value="0"/>



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         </xs:restriction>
        </xs:simpleType>
       </xs:attribute>
       <xs:attribute name="maxgain" default="10">
        <xs:simpleType>
         <xs:restriction base="xs:nonNegativeInteger">
          <xs:minInclusive value="0"/>
          <xs:maxInclusive value="40"/>
         </xs:restriction>
        </xs:simpleType>
       </xs:attribute>
      </xs:complexType>
     </xs:element>
     <xs:element name="clamp">
      <xs:complexType>
       <xs:attribute name="dtmf" type="boolean.datatype"/>
       <xs:attribute name="tones" type="boolean.datatype"/>
      </xs:complexType>
     </xs:element>
     <xs:element name="visual"/>
    </xs:choice>
    <xs:attribute name="preferred" type="boolean.datatype"
                  default="false"/>
    <xs:attribute name="display" type="xs:string"/>
    <xs:attribute name="override" type="boolean.datatype"
                  default="false"/>
   </xs:extension>
  </xs:complexContent>
 </xs:complexType>
 <xs:complexType name="basicAudioMixType">
  <xs:attribute name="id" type="xs:string" use="optional"/>
  <xs:attribute name="samplerate" type="xs:positiveInteger"
                use="optional" default="8000"/>
 </xs:complexType>
 <xs:complexType name="audioMixType">
  <xs:complexContent>
   <xs:extension base="basicAudioMixType">
    <xs:all>
     <xs:element name="asn" minOccurs="0">
      <xs:complexType>
       <xs:attribute name="ri" type="posDuration.datatype"/>
       <xs:attribute name="asth" default="-96">
        <xs:simpleType>
         <xs:restriction base="xs:nonPositiveInteger">
          <xs:minInclusive value="-96"/>
          <xs:maxInclusive value="0"/>
         </xs:restriction>
        </xs:simpleType>



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       </xs:attribute>
      </xs:complexType>
     </xs:element>
     <xs:element name="n-loudest" minOccurs="0">
      <xs:complexType>
       <xs:attribute name="n" type="xs:positiveInteger" use="required"/>
      </xs:complexType>
     </xs:element>
    </xs:all>
   </xs:extension>
  </xs:complexContent>
 </xs:complexType>
 <xs:complexType name="basicVideoLayoutType">
  <xs:attribute name="id" type="xs:string" use="required"/>
  <xs:attribute name="type" type="xs:string" use="required"
                fixed="text/msml-basic-layout"/>
 </xs:complexType>
 <xs:complexType name="videoLayoutType">
  <xs:complexContent>
   <xs:extension base="basicVideoLayoutType">
    <xs:choice>
     <xs:element name="selector">
      <xs:complexType>
       <xs:complexContent>
        <xs:extension base="selectorType">
         <xs:choice>
          <xs:element name="root" type="rootType" minOccurs="0"/>
          <xs:element name="region" minOccurs="0">
           <xs:complexType>
            <xs:attribute name="id" type="xs:string" use="required"/>
            <xs:attribute name="left" type="xs:positiveInteger"/>
            <xs:attribute name="top" type="xs:positiveInteger"/>
            <xs:attribute name="relativeSize">
             <xs:simpleType>
              <xs:restriction base="xs:string">
               <xs:enumeration value="1/4"/>
               <xs:enumeration value="1/3"/>
               <xs:enumeration value="2/3"/>
               <xs:enumeration value="3/4"/>
               <xs:enumeration value="1"/>
              </xs:restriction>
             </xs:simpleType>
            </xs:attribute>
            <xs:attribute name="priority">
             <xs:simpleType>
              <xs:restriction base="xs:float">
               <xs:minInclusive value="0"/>
               <xs:maxExclusive value="1"/>



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              </xs:restriction>
             </xs:simpleType>
            </xs:attribute>
            <xs:attribute name="title" type="xs:string"/>
            <xs:attribute name="titleTextColor" type="xs:string"/>
            <xs:attribute name="titleBackgroundColor" type="xs:string"/>
            <xs:attribute name="borderColor" type="xs:string"/>
            <xs:attribute name="borderWidth" type="xs:positiveInteger"/>
            <xs:attribute name="logo" type="xs:anyURI"/>
           </xs:complexType>
          </xs:element>
         </xs:choice>
        </xs:extension>
       </xs:complexContent>
      </xs:complexType>
     </xs:element>
     <xs:element name="root" type="rootType"/>
     <xs:element name="region" minOccurs="0" maxOccurs="unbounded">
      <xs:complexType>
       <xs:complexContent>
        <xs:extension base="regionType"/>
       </xs:complexContent>
      </xs:complexType>
     </xs:element>
    </xs:choice>
   </xs:extension>
  </xs:complexContent>
 </xs:complexType>
 <xs:complexType name="regionType">
  <xs:attribute name="id" type="xs:string" use="required"/>
  <xs:attribute name="left" type="xs:positiveInteger"/>
  <xs:attribute name="top" type="xs:positiveInteger"/>
  <xs:attribute name="relativeSize">
   <xs:simpleType>
    <xs:restriction base="xs:string">
     <xs:enumeration value="1/4"/>
     <xs:enumeration value="1/3"/>
     <xs:enumeration value="2/3"/>
     <xs:enumeration value="3/4"/>
     <xs:enumeration value="1"/>
    </xs:restriction>
   </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="priority">
   <xs:simpleType>
    <xs:restriction base="xs:float">
     <xs:minInclusive value="0"/>
     <xs:maxExclusive value="1"/>



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    </xs:restriction>
   </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="title" type="xs:string"/>
  <xs:attribute name="titleTextColor" type="xs:string"/>
  <xs:attribute name="titleBackgroundColor" type="xs:string"/>
  <xs:attribute name="borderColor" type="xs:string"/>
  <xs:attribute name="borderWidth" type="xs:positiveInteger"/>
  <xs:attribute name="logo" type="xs:anyURI"/>
 </xs:complexType>
 <xs:complexType name="selectorType">
  <xs:attribute name="id" type="xs:string" use="required"/>
  <xs:attribute name="method" use="required">
   <xs:simpleType>
    <xs:restriction base="xs:string">
     <xs:enumeration value="vas"/>
     <xs:enumeration value="sequence"/>
    </xs:restriction>
   </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="status" default="active">
   <xs:simpleType>
    <xs:restriction base="xs:string">
     <xs:enumeration value="active"/>
     <xs:enumeration value="disabled"/>
    </xs:restriction>
   </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="si" type="posDuration.datatype" default="1s"/>
  <xs:attribute name="blankothers" type="xs:boolean" default="false"/>
  <xs:attribute name="speakersees" default="current">
   <xs:simpleType>
    <xs:restriction base="xs:string">
     <xs:enumeration value="current"/>
     <xs:enumeration value="previous"/>
    </xs:restriction>
   </xs:simpleType>
  </xs:attribute>
 </xs:complexType>
 <xs:complexType name="rootType">
  <xs:attribute name="size" default="CIF">
   <xs:simpleType>
    <xs:restriction base="xs:string">
     <xs:enumeration value="16CIF"/>
     <xs:enumeration value="4CIF"/>
     <xs:enumeration value="CIF"/>
     <xs:enumeration value="QCIF"/>
    </xs:restriction>



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   </xs:simpleType>
  </xs:attribute>
  <xs:attribute name="backgroundcolor" type="xs:string"
                default="black"/>
  <xs:attribute name="backgroundimage" type="xs:anyURI"/>
 </xs:complexType>
 <xs:simpleType name="confclass.datatype">
  <xs:restriction base="xs:string">
   <xs:enumeration value="standard"/>
   <xs:enumeration value="preferred"/>
  </xs:restriction>
 </xs:simpleType>
 <xs:simpleType name="conferenceType.datatype">
  <xs:restriction base="xs:string">
   <xs:enumeration value="audio.basic"/>
   <xs:enumeration value="audio.advanced"/>
  </xs:restriction>
 </xs:simpleType>
 <xs:simpleType name="duplex.datatype">
  <xs:restriction base="xs:string">
   <xs:enumeration value="half"/>
   <xs:enumeration value="full"/>
  </xs:restriction>
 </xs:simpleType>
</xs:schema>

16.3.  MSML Dialog Packages

16.3.1.  msml-dialog-core.xsd

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
           elementFormDefault="qualified"
           attributeFormDefault="unqualified">
 <xs:include schemaLocation="msml-core.xsd"/>
 <xs:include schemaLocation="msml-dialog-core-datatypes.xsd"/>
</xs:schema>

16.3.2.  msml-dialog-core-datatypes.xsd

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
           elementFormDefault="qualified"
           attributeFormDefault="unqualified">
 <xs:include schemaLocation="msml-core-datatypes.xsd"/>
 <xs:group name="momlRequest">
  <xs:choice>
   <xs:group ref="executeType"/>



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   <xs:group ref="sendType"/>
  </xs:choice>
 </xs:group>
 <xs:element name="dialogstart" substitutionGroup="msmlRequest">
  <xs:complexType>
   <xs:complexContent>
    <xs:extension base="msmlRequestType">
     <xs:choice>
      <xs:group ref="momlRequest" minOccurs="0"/>
     </xs:choice>
     <xs:attribute name="target" type="independentID.datatype"
                   use="required"/>
     <xs:attribute name="type" type="dialogLanguage.datatype"
                   use="required"/>
     <xs:attribute name="name" type="msmlInstanceID.datatype"/>
     <xs:attribute name="src" type="xs:anyURI" use="optional"/>
    </xs:extension>
   </xs:complexContent>
  </xs:complexType>
 </xs:element>
 <xs:element name="dialogend" substitutionGroup="msmlRequest">
  <xs:complexType>
   <xs:complexContent>
    <xs:extension base="msmlRequestType">
     <xs:attribute name="id" type="dialogID.datatype" use="required"/>
    </xs:extension>
   </xs:complexContent>
  </xs:complexType>
 </xs:element>
 <xs:element name="dialogid" type="msmlResultSimpleType"
             substitutionGroup="msmlResultSimple"/>
 <xs:group name="executeType">
  <xs:choice>
   <xs:element ref="primitive" maxOccurs="unbounded"/>
   <xs:element ref="control" maxOccurs="unbounded"/>
  </xs:choice>
 </xs:group>
 <xs:element name="primitive" type="primitiveType" abstract="true"/>
 <xs:complexType name="primitiveType">
  <xs:attribute name="id" type="momlID.datatype"/>
 </xs:complexType>
 <xs:element name="control" abstract="true"/>
 <xs:group name="sendType">
  <xs:choice>
   <xs:choice>
    <xs:element name="exit" type="exitType"/>
    <xs:element name="disconnect" type="exitType"/>
   </xs:choice>



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   <xs:sequence>
    <xs:element ref="send" maxOccurs="unbounded"/>
    <xs:choice minOccurs="0">
     <xs:element name="exit" type="exitType"/>
     <xs:element name="disconnect" type="exitType"/>
    </xs:choice>
   </xs:sequence>
  </xs:choice>
 </xs:group>
 <xs:element name="send">
  <xs:complexType>
   <xs:attribute name="event" type="momlEvent.datatype" use="required"/>
   <xs:attribute name="target" type="momlTarget.datatype"
                 use="required"/>
   <xs:attribute name="namelist" type="momlNamelist.datatype"/>
  </xs:complexType>
 </xs:element>
 <xs:complexType name="exitType">
  <xs:attribute name="namelist" type="momlNamelist.datatype"/>
 </xs:complexType>
 <xs:simpleType name="momlID.datatype">
  <xs:restriction base="xs:string">
   <xs:pattern value="[a-zA-Z0-9][a-zA-Z0-9._\-]*"/>
  </xs:restriction>
 </xs:simpleType>
 <xs:simpleType name="momlEvent.datatype">
  <xs:restriction base="xs:string">
   <xs:pattern value="[a-zA-Z0-9][a-zA-Z0-9._\-]*"/>
  </xs:restriction>
 </xs:simpleType>
 <xs:simpleType name="momlNamelist.datatype">
  <xs:restriction base="xs:string"/>
 </xs:simpleType>
 <xs:simpleType name="dtmfDigits.datatype">
  <xs:restriction base="xs:string">
   <xs:pattern value="[0-9#*]+"/>
  </xs:restriction>
 </xs:simpleType>
 <xs:simpleType name="iterate.datatype">
  <xs:union memberTypes="xs:positiveInteger">
   <xs:simpleType>
    <xs:restriction base="xs:negativeInteger">
     <xs:minInclusive value="-1"/>
    </xs:restriction>
   </xs:simpleType>
   <xs:simpleType>
    <xs:restriction base="xs:string">
     <xs:enumeration value="forever"/>



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    </xs:restriction>
   </xs:simpleType>
  </xs:union>
 </xs:simpleType>
 <xs:simpleType name="momlTarget.datatype">
  <xs:restriction base="xs:string">
   <xs:pattern value="[a-zA-Z0-9][a-zA-Z0-9._\-]*"/>
  </xs:restriction>
 </xs:simpleType>
 <xs:simpleType name="duration.datatype">
  <xs:restriction base="xs:string">
   <xs:pattern value="(\+|\-)?([0-9]*\.)?[0-9]+(ms|s)"/>
  </xs:restriction>
 </xs:simpleType>
</xs:schema>

16.3.3.  msml-dialog-base.xsd

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
           elementFormDefault="unqualified"
           attributeFormDefault="unqualified">
 <xs:include schemaLocation="msml-core.xsd"/>
 <xs:include schemaLocation="msml-dialog-core-datatypes.xsd"/>
 <xs:include schemaLocation="msml-dialog-base-datatypes.xsd"/>
</xs:schema>

16.3.4.  msml-dialog-base-datatypes.xsd

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
           elementFormDefault="unqualified"
           attributeFormDefault="unqualified">
 <xs:include schemaLocation="msml-dialog-core-datatypes.xsd"/>
 <xs:import namespace="http://www.w3.org/XML/1998/namespace"
            schemaLocation="http://www.w3.org/2001/xml.xsd"/>
 <xs:element name="play" substitutionGroup="primitive">
  <xs:complexType>
   <xs:complexContent>
    <xs:extension base="primitiveType">
     <xs:sequence>
      <xs:choice maxOccurs="unbounded">
       <xs:element name="audio" minOccurs="0" maxOccurs="unbounded">
        <xs:complexType>
         <xs:attribute name="uri" type="xs:anyURI" use="required"/>
         <xs:attribute name="iterate" type="iterate.datatype"
                       default="1"/>
         <xs:attribute name="format" type="xs:string" use="optional"/>



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         <xs:attribute name="audiosamplerate" type="xs:positiveInteger"
                       use="optional"/>
         <xs:attribute name="audiosamplesize" type="xs:positiveInteger"
                       use="optional"/>
         <xs:attribute ref="xml:lang"/>
        </xs:complexType>
       </xs:element>
       <xs:element name="video" minOccurs="0" maxOccurs="unbounded">
        <xs:complexType>
         <xs:attribute name="uri" type="xs:anyURI" use="required"/>
         <xs:attribute name="iterate" type="iterate.datatype"
                       use="optional" default="1"/>
         <xs:attribute name="format" type="xs:string" use="optional"/>
         <xs:attribute name="audiosamplerate" type="xs:positiveInteger"
                       use="optional"/>
         <xs:attribute name="audiosamplesize" type="xs:positiveInteger"
                       use="optional"/>
         <xs:attribute name="codecconfig" type="xs:string"
                       use="optional"/>
         <xs:attribute name="profile" type="xs:string" use="optional"/>
         <xs:attribute name="level" type="xs:string" use="optional"/>
         <xs:attribute name="imagewidth" type="xs:positiveInteger"
                       use="optional"/>
         <xs:attribute name="imageheight" type="xs:positiveInteger"
                       use="optional"/>
         <xs:attribute name="maxbitrate" type="xs:positiveInteger"
                       use="optional"/>
         <xs:attribute name="framerate" type="xs:positiveInteger"
                       use="optional"/>
        </xs:complexType>
       </xs:element>
       <xs:element name="media" minOccurs="0" maxOccurs="unbounded">
        <xs:complexType>
         <xs:choice minOccurs="0" maxOccurs="unbounded">
          <xs:element name="audio" minOccurs="0">
           <xs:complexType>
            <xs:attribute name="uri" type="xs:anyURI" use="required"/>
            <xs:attribute name="iterate" type="iterate.datatype"
                          default="1"/>
            <xs:attribute name="format" type="xs:string"
                          use="optional"/>
            <xs:attribute name="audiosamplerate"
                          type="xs:positiveInteger" use="optional"/>
            <xs:attribute name="audiosamplesize"
                          type="xs:positiveInteger" use="optional"/>
            <xs:attribute ref="xml:lang"/>
           </xs:complexType>
          </xs:element>



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          <xs:element name="video" minOccurs="0">
           <xs:complexType>
            <xs:attribute name="uri" type="xs:anyURI" use="required"/>
            <xs:attribute name="iterate" type="iterate.datatype"
                          use="optional" default="1"/>
            <xs:attribute name="format" type="xs:string"
                          use="optional"/>
            <xs:attribute name="audiosamplerate"
                          type="xs:positiveInteger" use="optional"/>
            <xs:attribute name="audiosamplesize"
                          type="xs:positiveInteger" use="optional"/>
            <xs:attribute name="codecconfig" type="xs:string"
                          use="optional"/>
            <xs:attribute name="profile" type="xs:string"
                          use="optional"/>
            <xs:attribute name="level" type="xs:string" use="optional"/>
            <xs:attribute name="imagewidth" type="xs:positiveInteger"
                          use="optional"/>
            <xs:attribute name="imageheight" type="xs:positiveInteger"
                          use="optional"/>
            <xs:attribute name="maxbitrate" type="xs:positiveInteger"
                          use="optional"/>
            <xs:attribute name="framerate" type="xs:positiveInteger"
                          use="optional"/>
           </xs:complexType>
          </xs:element>
         </xs:choice>
        </xs:complexType>
       </xs:element>
       <xs:element ref="smedia" minOccurs="0" maxOccurs="unbounded"/>
      </xs:choice>
      <xs:choice minOccurs="0">
       <xs:element name="playexit">
        <xs:complexType>
         <xs:group ref="sendType"/>
        </xs:complexType>
       </xs:element>
      </xs:choice>
     </xs:sequence>
     <xs:attribute name="interval" type="posDuration.datatype"
                   use="optional"/>
     <xs:attribute name="iterate" type="iterate.datatype" use="optional"
                   default="1"/>
     <xs:attribute name="offset" type="duration.datatype"
                   use="optional"/>
     <xs:attribute name="initial" use="optional" default="generate">
      <xs:simpleType>
       <xs:restriction base="xs:string">



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        <xs:enumeration value="generate"/>
        <xs:enumeration value="suspend"/>
       </xs:restriction>
      </xs:simpleType>
     </xs:attribute>
     <xs:attribute name="maxtime" type="posDuration.datatype"
                   use="optional"/>
     <xs:attribute name="skip" type="duration.datatype" use="optional"
                   default="3s"/>
     <xs:attribute name="barge" type="boolean.datatype" use="optional"
                   default="false"/>
     <xs:attribute name="cleardb" type="boolean.datatype" use="optional"
                   default="false"/>
     <xs:attribute ref="xml:lang"/>
    </xs:extension>
   </xs:complexContent>
  </xs:complexType>
 </xs:element>
 <xs:element name="record" substitutionGroup="primitive">
  <xs:complexType>
   <xs:complexContent>
    <xs:extension base="primitiveType">
     <xs:choice minOccurs="0">
      <xs:element ref="play" minOccurs="0" maxOccurs="unbounded"/>
      <xs:element ref="tonegen" minOccurs="0" maxOccurs="unbounded"/>
      <xs:element name="recordexit">
       <xs:complexType>
        <xs:group ref="sendType"/>
       </xs:complexType>
      </xs:element>
     </xs:choice>
     <xs:attribute name="append" type="boolean.datatype" use="optional"
                   default="false"/>
     <xs:attribute name="dest" type="xs:anyURI" use="optional"/>
     <xs:attribute name="audiodest" type="xs:anyURI" use="optional"/>
     <xs:attribute name="videodest" type="xs:anyURI" use="optional"/>
     <xs:attribute name="format" use="required">
      <xs:simpleType>
       <xs:restriction base="xs:string"/>
      </xs:simpleType>
     </xs:attribute>
     <xs:attribute name="codecconfig" use="optional">
      <xs:simpleType>
       <xs:restriction base="xs:string"/>
      </xs:simpleType>
     </xs:attribute>
     <xs:attribute name="audiosamplerate" type="xs:positiveInteger"
                   use="optional"/>



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     <xs:attribute name="audiosamplesize" type="xs:positiveInteger"
                   use="optional"/>
     <xs:attribute name="profile" use="optional">
      <xs:simpleType>
       <xs:restriction base="xs:string"/>
      </xs:simpleType>
     </xs:attribute>
     <xs:attribute name="level" use="optional">
      <xs:simpleType>
       <xs:restriction base="xs:string"/>
      </xs:simpleType>
     </xs:attribute>
     <xs:attribute name="imagewidth" type="xs:positiveInteger"
                   use="optional"/>
     <xs:attribute name="imageheight" type="xs:positiveInteger"
                   use="optional"/>
     <xs:attribute name="maxbitrate" type="xs:positiveInteger"
                   use="optional"/>
     <xs:attribute name="framerate" type="xs:positiveInteger"
                   use="optional"/>
     <xs:attribute name="maxtime" type="posDuration.datatype"
                   use="required"/>
     <xs:attribute name="initial" use="optional" default="create">
      <xs:simpleType>
       <xs:restriction base="xs:string">
        <xs:enumeration value="create"/>
        <xs:enumeration value="suspend"/>
       </xs:restriction>
      </xs:simpleType>
     </xs:attribute>
     <xs:attribute name="prespeech" type="posDuration.datatype"
                   use="optional" default="0s"/>
     <xs:attribute name="postspeech" type="posDuration.datatype"
                   use="optional" default="0s"/>
     <xs:attribute name="termkey" use="optional">
      <xs:simpleType>
       <xs:restriction base="xs:string">
        <xs:pattern value="[0-9#*ABCD]"/>
       </xs:restriction>
      </xs:simpleType>
     </xs:attribute>
    </xs:extension>
   </xs:complexContent>
  </xs:complexType>
 </xs:element>
 <xs:element name="dtmf" substitutionGroup="primitive">
  <xs:complexType>
   <xs:complexContent>



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    <xs:extension base="primitiveType">
     <xs:sequence>
      <xs:element name="pattern" maxOccurs="unbounded">
       <xs:complexType>
        <xs:group ref="sendType"/>
        <xs:attribute name="digits" type="xs:string" use="required"/>
        <xs:attribute name="format">
         <xs:simpleType>
          <xs:restriction base="xs:string">
           <xs:enumeration value="mgcp"/>
           <xs:enumeration value="megaco"/>
           <xs:enumeration value="moml+digits"/>
          </xs:restriction>
         </xs:simpleType>
        </xs:attribute>
        <xs:attribute name="iterate" type="iterate.datatype"
                      default="1"/>
       </xs:complexType>
      </xs:element>
      <xs:element name="detect" minOccurs="0">
       <xs:complexType>
        <xs:group ref="sendType"/>
       </xs:complexType>
      </xs:element>
      <xs:element name="noinput" type="iterateSendType" minOccurs="0"/>
      <xs:element name="nomatch" type="iterateSendType" minOccurs="0"/>
      <xs:element name="dtmfexit" minOccurs="0">
       <xs:complexType>
        <xs:group ref="sendType"/>
       </xs:complexType>
      </xs:element>
      <xs:element ref="play" minOccurs="0"/>
     </xs:sequence>
     <xs:attribute name="cleardb" type="boolean.datatype"
                   default="true"/>
     <xs:attribute name="fdt" type="posDuration.datatype" default="0s"/>
     <xs:attribute name="idt" type="posDuration.datatype" default="4s"/>
     <xs:attribute name="edt" type="posDuration.datatype" default="4s"/>
     <xs:attribute name="starttimer" type="boolean.datatype"
                   default="false"/>
     <xs:attribute name="iterate" type="iterate.datatype" default="1"/>
     <xs:attribute name="ldd" type="posDuration.datatype" default="0s"/>
    </xs:extension>
   </xs:complexContent>
  </xs:complexType>
 </xs:element>
 <xs:element name="collect" substitutionGroup="primitive">
  <xs:complexType>



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   <xs:complexContent>
    <xs:extension base="primitiveType">
     <xs:sequence>
      <xs:element name="pattern" maxOccurs="unbounded">
       <xs:complexType>
        <xs:group ref="sendType"/>
        <xs:attribute name="digits" type="xs:string" use="required"/>
        <xs:attribute name="format">
         <xs:simpleType>
          <xs:restriction base="xs:string">
           <xs:enumeration value="mgcp"/>
           <xs:enumeration value="megaco"/>
           <xs:enumeration value="moml+digits"/>
          </xs:restriction>
         </xs:simpleType>
        </xs:attribute>
        <xs:attribute name="iterate" type="iterate.datatype"
                      default="1"/>
       </xs:complexType>
      </xs:element>
      <xs:element name="detect" minOccurs="0">
       <xs:complexType>
        <xs:group ref="sendType"/>
       </xs:complexType>
      </xs:element>
      <xs:element name="noinput" type="iterateSendType" minOccurs="0"/>
      <xs:element name="nomatch" type="iterateSendType" minOccurs="0"/>
      <xs:element name="dtmfexit" minOccurs="0">
       <xs:complexType>
        <xs:group ref="sendType"/>
       </xs:complexType>
      </xs:element>
      <xs:element ref="play" minOccurs="0"/>
     </xs:sequence>
     <xs:attribute name="cleardb" type="boolean.datatype"
                   default="true"/>
     <xs:attribute name="fdt" type="posDuration.datatype" default="0s"/>
     <xs:attribute name="idt" type="posDuration.datatype" default="4s"/>
     <xs:attribute name="edt" type="posDuration.datatype" default="4s"/>
     <xs:attribute name="starttimer" type="boolean.datatype"
                   default="false"/>
     <xs:attribute name="iterate" type="iterate.datatype" default="1"/>
     <xs:attribute name="ldd" type="posDuration.datatype"/>
    </xs:extension>
   </xs:complexContent>
  </xs:complexType>
 </xs:element>
 <xs:element name="dtmfgen" substitutionGroup="primitive">



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  <xs:complexType>
   <xs:complexContent>
    <xs:extension base="primitiveType">
     <xs:choice minOccurs="0">
      <xs:element name="dtmfgenexit">
       <xs:complexType>
        <xs:group ref="sendType"/>
       </xs:complexType>
      </xs:element>
     </xs:choice>
     <xs:attribute name="level" use="optional" default="-6">
      <xs:simpleType>
       <xs:restriction base="xs:nonPositiveInteger">
        <xs:maxInclusive value="0"/>
        <xs:minInclusive value="-96"/>
       </xs:restriction>
      </xs:simpleType>
     </xs:attribute>
     <xs:attribute name="digits" type="dtmfDigits.datatype"
                   use="required"/>
     <xs:attribute name="dur" type="posDuration.datatype" use="optional"
                   default="100ms"/>
     <xs:attribute name="interval" type="posDuration.datatype"
                   use="optional" default="100ms"/>
    </xs:extension>
   </xs:complexContent>
  </xs:complexType>
 </xs:element>
 <xs:element name="tonegen" substitutionGroup="primitive">
  <xs:complexType>
   <xs:complexContent>
    <xs:extension base="primitiveType">
     <xs:choice minOccurs="0">
      <xs:element name="tonegenexit" minOccurs="0">
       <xs:complexType>
        <xs:group ref="sendType"/>
       </xs:complexType>
      </xs:element>
      <xs:element name="tone" maxOccurs="unbounded">
       <xs:complexType>
        <xs:sequence>
         <xs:element name="tone1">
          <xs:complexType>
           <xs:attribute name="freq" use="required">
            <xs:simpleType>
             <xs:restriction base="xs:unsignedInt">
              <xs:minInclusive value="0"/>
              <xs:maxInclusive value="3999"/>



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             </xs:restriction>
            </xs:simpleType>
           </xs:attribute>
           <xs:attribute name="atten" use="required">
            <xs:simpleType>
             <xs:restriction base="xs:nonPositiveInteger">
              <xs:minInclusive value="-96"/>
              <xs:maxInclusive value="0"/>
             </xs:restriction>
            </xs:simpleType>
           </xs:attribute>
          </xs:complexType>
         </xs:element>
         <xs:element name="tone2">
          <xs:complexType>
           <xs:attribute name="freq" use="required">
            <xs:simpleType>
             <xs:restriction base="xs:unsignedInt">
              <xs:minInclusive value="0"/>
              <xs:maxInclusive value="3999"/>
             </xs:restriction>
            </xs:simpleType>
           </xs:attribute>
           <xs:attribute name="atten" use="required">
            <xs:simpleType>
             <xs:restriction base="xs:nonPositiveInteger">
              <xs:minInclusive value="-96"/>
              <xs:maxInclusive value="0"/>
             </xs:restriction>
            </xs:simpleType>
           </xs:attribute>
          </xs:complexType>
         </xs:element>
         <xs:element name="silence" minOccurs="0" maxOccurs="unbounded">
          <xs:complexType>
           <xs:attribute name="duration" type="duration.datatype"
                         use="required"/>
          </xs:complexType>
         </xs:element>
        </xs:sequence>
        <xs:attribute name="duration" use="required">
         <xs:simpleType>
          <xs:restriction base="duration.datatype"/>
         </xs:simpleType>
        </xs:attribute>
        <xs:attribute name="iterate" type="iterate.datatype"
                      use="optional" default="1"/>
       </xs:complexType>



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      </xs:element>
      <xs:element name="silence" minOccurs="0" maxOccurs="unbounded">
       <xs:complexType>
        <xs:attribute name="duration" type="duration.datatype"
                      use="required"/>
       </xs:complexType>
      </xs:element>
     </xs:choice>
     <xs:attribute name="iterate" type="iterate.datatype" use="optional"
                   default="1"/>
    </xs:extension>
   </xs:complexContent>
  </xs:complexType>
 </xs:element>
 <xs:complexType name="iterateSendType">
  <xs:group ref="sendType"/>
  <xs:attribute name="iterate" type="iterate.datatype" default="1"/>
 </xs:complexType>
 <xs:element name="smedia" type="smediaType" abstract="true"/>
 <xs:complexType name="smediaType">
  <xs:attribute ref="xml:lang"/>
  <xs:attribute name="iterate" type="iterate.datatype"/>
 </xs:complexType>
 <xs:element name="var" substitutionGroup="smedia">
  <xs:complexType>
   <xs:complexContent>
    <xs:extension base="smediaType">
     <xs:attribute name="type" use="required">
      <xs:simpleType>
       <xs:restriction base="xs:string">
        <xs:enumeration value="date"/>
        <xs:enumeration value="digits"/>
        <xs:enumeration value="duration"/>
        <xs:enumeration value="month"/>
        <xs:enumeration value="money"/>
        <xs:enumeration value="number"/>
        <xs:enumeration value="silence"/>
        <xs:enumeration value="time"/>
        <xs:enumeration value="weekday"/>
       </xs:restriction>
      </xs:simpleType>
     </xs:attribute>
     <xs:attribute name="subtype" type="xs:string" use="optional"/>
     <xs:attribute name="value" type="xs:string" use="required"/>
    </xs:extension>
   </xs:complexContent>





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  </xs:complexType>
 </xs:element>
</xs:schema>

16.3.5.  msml-dialog-transform.xsd

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
           elementFormDefault="unqualified"
           attributeFormDefault="unqualified">
 <xs:include schemaLocation="msml-core.xsd"/>
 <xs:include schemaLocation="msml-dialog-core-datatypes.xsd"/>
 <xs:include schemaLocation="msml-dialog-transform-datatypes.xsd"/>
</xs:schema>

16.3.6.  msml-dialog-transform-datatypes.xsd

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
           elementFormDefault="unqualified"
           attributeFormDefault="unqualified">
 <xs:include schemaLocation="msml-dialog-core-datatypes.xsd"/>
 <xs:import namespace="http://www.w3.org/XML/1998/namespace"
            schemaLocation="http://www.w3.org/2001/xml.xsd"/>
 <xs:element name="vad" substitutionGroup="primitive">
  <xs:complexType>
   <xs:complexContent>
    <xs:extension base="primitiveType">
     <xs:all>
      <xs:element name="voice" type="vadPatternType" minOccurs="0"/>
      <xs:element name="silence" type="vadPatternType" minOccurs="0"/>
      <xs:element name="tvoice" type="vadPatternType" minOccurs="0"/>
      <xs:element name="tsilence" type="vadPatternType" minOccurs="0"/>
     </xs:all>
     <xs:attribute name="starttimer" type="boolean.datatype"
                   default="false"/>
    </xs:extension>
   </xs:complexContent>
  </xs:complexType>
 </xs:element>
 <xs:element name="gain" substitutionGroup="primitive">
  <xs:complexType>
   <xs:complexContent>
    <xs:extension base="primitiveType">
     <xs:attribute name="incr" default="3">
      <xs:simpleType>
       <xs:restriction base="xs:positiveInteger">
        <xs:maxInclusive value="96"/>



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       </xs:restriction>
      </xs:simpleType>
     </xs:attribute>
     <xs:attribute name="amt" use="required">
      <xs:simpleType>
       <xs:restriction base="xs:integer">
        <xs:minInclusive value="-96"/>
        <xs:maxInclusive value="96"/>
       </xs:restriction>
      </xs:simpleType>
     </xs:attribute>
    </xs:extension>
   </xs:complexContent>
  </xs:complexType>
 </xs:element>
 <xs:element name="agc" substitutionGroup="primitive">
  <xs:complexType>
   <xs:complexContent>
    <xs:extension base="primitiveType">
     <xs:attribute name="tgtlvl" use="required">
      <xs:simpleType>
       <xs:restriction base="xs:nonPositiveInteger">
        <xs:minInclusive value="-40"/>
        <xs:maxInclusive value="0"/>
       </xs:restriction>
      </xs:simpleType>
     </xs:attribute>
     <xs:attribute name="maxgain" default="10">
      <xs:simpleType>
       <xs:restriction base="xs:nonNegativeInteger">
        <xs:minInclusive value="0"/>
        <xs:maxInclusive value="40"/>
       </xs:restriction>
      </xs:simpleType>
     </xs:attribute>
    </xs:extension>
   </xs:complexContent>
  </xs:complexType>
 </xs:element>
 <xs:element name="gate" substitutionGroup="primitive">
  <xs:complexType>
   <xs:complexContent>
    <xs:extension base="primitiveType">
     <xs:attribute name="initial" default="pass">
      <xs:simpleType>
       <xs:restriction base="xs:string">
        <xs:enumeration value="pass"/>
        <xs:enumeration value="halt"/>



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       </xs:restriction>
      </xs:simpleType>
     </xs:attribute>
    </xs:extension>
   </xs:complexContent>
  </xs:complexType>
 </xs:element>
 <xs:element name="clamp" substitutionGroup="primitive">
  <xs:complexType>
   <xs:complexContent>
    <xs:extension base="primitiveType"/>
   </xs:complexContent>
  </xs:complexType>
 </xs:element>
 <xs:element name="relay" substitutionGroup="primitive">
  <xs:complexType>
   <xs:complexContent>
    <xs:extension base="primitiveType"/>
   </xs:complexContent>
  </xs:complexType>
 </xs:element>
 <xs:complexType name="vadPatternType">
  <xs:group ref="sendType"/>
  <xs:attribute name="iterate" type="iterate.datatype" default="1"/>
  <xs:attribute name="len" type="posDuration.datatype" use="required"/>
  <xs:attribute name="sen" type="posDuration.datatype" use="optional"/>
 </xs:complexType>
</xs:schema>

16.3.7.  msml-dialog-group.xsd

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
           elementFormDefault="unqualified"
           attributeFormDefault="unqualified">
 <xs:include schemaLocation="msml-core.xsd"/>
 <xs:include schemaLocation="msml-dialog-core-datatypes.xsd"/>
 <xs:include schemaLocation="msml-dialog-base-datatypes.xsd"/>
 <xs:include schemaLocation="msml-dialog-group-datatypes.xsd"/>
</xs:schema>

16.3.8.  msml-dialog-group-datatypes.xsd

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
           elementFormDefault="unqualified"
           attributeFormDefault="unqualified">
 <xs:include schemaLocation="msml-core-datatypes.xsd"/>



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 <xs:include schemaLocation="msml-dialog-core-datatypes.xsd"/>
 <xs:include schemaLocation="msml-dialog-base-datatypes.xsd"/>
 <xs:include schemaLocation="msml-dialog-transform-datatypes.xsd"/>
 <xs:element name="group" substitutionGroup="control">
  <xs:complexType>
   <xs:sequence>
    <xs:group ref="executeType"/>
    <xs:element name="groupexit" minOccurs="0">
     <xs:complexType>
      <xs:group ref="sendType"/>
     </xs:complexType>
    </xs:element>
   </xs:sequence>
   <xs:attribute name="id" type="momlID.datatype"/>
   <xs:attribute name="topology" use="required">
    <xs:simpleType>
     <xs:restriction base="xs:string">
      <xs:enumeration value="serial"/>
      <xs:enumeration value="parallel"/>
      <xs:enumeration value="fullduplex"/>
     </xs:restriction>
    </xs:simpleType>
   </xs:attribute>
  </xs:complexType>
 </xs:element>
</xs:schema>

16.3.9.  msml-dialog-speech.xsd

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
           elementFormDefault="qualified"
           attributeFormDefault="unqualified">
 <xs:include schemaLocation="msml-core.xsd"/>
 <xs:include schemaLocation="msml-dialog-core-datatypes.xsd"/>
 <xs:include schemaLocation="msml-dialog-base-datatypes.xsd"/>
 <xs:include schemaLocation="msml-dialog-speech-datatypes.xsd"/>
</xs:schema>

16.3.10.  msml-dialog-speech-datatypes.xsd

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
           elementFormDefault="qualified"
           attributeFormDefault="unqualified">
 <xs:include schemaLocation="msml-dialog-core-datatypes.xsd"/>
 <xs:include schemaLocation="msml-dialog-base-datatypes.xsd"/>
 <xs:include schemaLocation="http://www.w3.org/TR/2002/WD-speech-



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             synthesis-20020405/synthesis-core.xsd"/>
 <xs:include schemaLocation="http://www.w3.org/TR/speech-
             grammar/grammar-core.xsd"/>
 <xs:element name="speech" substitutionGroup="primitive">
  <xs:complexType>
   <xs:complexContent>
    <xs:extension base="primitiveType">
     <xs:sequence>
      <xs:element name="grammar" maxOccurs="unbounded">
       <xs:complexType>
        <xs:complexContent>
         <xs:extension base="grammar">
          <xs:choice>
           <xs:element name="match" type="iterateSendType"
                       minOccurs="0"/>
          </xs:choice>
          <xs:attribute name="uri" type="xs:anyURI"/>
          <xs:attribute name="iterate" type="iterate.datatype"
                        default="1"/>
         </xs:extension>
        </xs:complexContent>
       </xs:complexType>
      </xs:element>
      <xs:element name="noinput" type="iterateSendType" minOccurs="0"/>
      <xs:element name="nomatch" type="iterateSendType" minOccurs="0"/>
      <xs:element name="speechexit" minOccurs="0">
       <xs:complexType>
        <xs:group ref="sendType"/>
       </xs:complexType>
      </xs:element>
     </xs:sequence>
     <xs:attribute name="noint" type="posDuration.datatype"/>
     <xs:attribute name="norect" type="posDuration.datatype"/>
     <xs:attribute name="spcmplt" type="posDuration.datatype"/>
     <xs:attribute name="confidence">
      <xs:simpleType>
       <xs:restriction base="xs:positiveInteger">
        <xs:maxInclusive value="100"/>
       </xs:restriction>
      </xs:simpleType>
     </xs:attribute>
     <xs:attribute name="sens" type="xs:positiveInteger"/>
     <xs:attribute name="starttimer" type="boolean.datatype"
                   default="false"/>
     <xs:attribute name="iterate" type="iterate.datatype" default="1"/>
    </xs:extension>
   </xs:complexContent>
  </xs:complexType>



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 </xs:element>
 <xs:element name="tts" type="smediaType" substitutionGroup="smedia"/>
</xs:schema>

16.3.11.  msml-dialog-fax-detect.xsd

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
           elementFormDefault="qualified"
           attributeFormDefault="unqualified">
 <xs:include schemaLocation="msml-core.xsd"/>
 <xs:include schemaLocation="msml-dialog-core-datatypes.xsd"/>
 <xs:include schemaLocation="msml-dialog-fax-detect-datatypes.xsd"/>
</xs:schema>

16.3.12.  msml-dialog-fax-detect-datatypes.xsd

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
           elementFormDefault="qualified"
           attributeFormDefault="unqualified">
 <xs:include schemaLocation="msml-dialog-core-datatypes.xsd"/>
 <xs:element name="faxdetect" substitutionGroup="primitive">
  <xs:complexType>
   <xs:complexContent>
    <xs:extension base="primitiveType">
     <xs:choice minOccurs="0">
      <xs:element name="faxdetectexit">
       <xs:complexType>
        <xs:group ref="sendType"/>
       </xs:complexType>
      </xs:element>
     </xs:choice>
    </xs:extension>
   </xs:complexContent>
  </xs:complexType>
 </xs:element>
</xs:schema>

16.3.13.  msml-dialog-fax-sendrecv.xsd

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
           elementFormDefault="qualified"
           attributeFormDefault="unqualified">
 <xs:include schemaLocation="msml-core.xsd"/>
 <xs:include schemaLocation="msml-dialog-core-datatypes.xsd"/>
 <xs:include schemaLocation="msml-dialog-fax-sendrecv-datatypes.xsd"/>



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</xs:schema>

16.3.14.  msml-dialog-fax-sendrecv-datatypes.xsd

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
           elementFormDefault="qualified"
           attributeFormDefault="unqualified">
 <xs:include schemaLocation="msml-dialog-core-datatypes.xsd"/>
 <xs:element name="faxsend" substitutionGroup="primitive">
  <xs:complexType>
   <xs:complexContent>
    <xs:extension base="primitiveType">
     <xs:sequence>
      <xs:element name="sendobj" type="sendobjType" minOccurs="0"
          maxOccurs="unbounded"/>
      <xs:element name="hdrfooter" type="hdrfooterType" minOccurs="0"/>
      <xs:element name="rxpoll" minOccurs="0">
       <xs:complexType>
        <xs:sequence>
         <xs:element name="rcvobj" type="rcvobjType"
                     maxOccurs="unbounded"/>
         <xs:element name="hdrfooter" type="hdrfooterType"
                     minOccurs="0"/>
        </xs:sequence>
        <xs:attribute name="rmtid" type="faxid.datatype"
                      use="required"/>
       </xs:complexType>
      </xs:element>
      <xs:group ref="faxstatusrequest"/>
     </xs:sequence>
     <xs:attribute name="lclid" type="faxid.datatype" use="optional"/>
     <xs:attribute name="minspeed" type="faxspeed.datatype"
                   use="optional"/>
     <xs:attribute name="maxspeed" type="faxspeed.datatype"
                   use="optional"/>
     <xs:attribute name="ecm" type="boolean.datatype" use="optional"/>
    </xs:extension>
   </xs:complexContent>
  </xs:complexType>
 </xs:element>
 <xs:element name="faxrecv" substitutionGroup="primitive">
  <xs:complexType>
   <xs:complexContent>
    <xs:extension base="primitiveType">
     <xs:sequence>
      <xs:element name="rcvobj" type="rcvobjType" minOccurs="0"
                  maxOccurs="unbounded"/>



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      <xs:element name="hdrfooter" type="hdrfooterType" minOccurs="0"/>
      <xs:element name="txpoll" minOccurs="0">
       <xs:complexType>
        <xs:sequence>
         <xs:element name="sendobj" type="sendobjType"
                     maxOccurs="unbounded"/>
         <xs:element name="hdrfooter" type="hdrfooterType"
                     minOccurs="0"/>
        </xs:sequence>
        <xs:attribute name="rmtid" type="faxid.datatype"/>
       </xs:complexType>
      </xs:element>
      <xs:group ref="faxstatusrequest"/>
     </xs:sequence>
     <xs:attribute name="lclid" type="faxid.datatype" use="optional"/>
     <xs:attribute name="ecm" type="boolean.datatype" default="true"/>
    </xs:extension>
   </xs:complexContent>
  </xs:complexType>
 </xs:element>
 <xs:group name="faxstatusrequest">
  <xs:sequence>
   <xs:element name="faxstart" minOccurs="0"/>
   <xs:element name="faxnegotiate" minOccurs="0"/>
   <xs:element name="faxpagedone" minOccurs="0"/>
   <xs:element name="faxobjectdone" minOccurs="0"/>
   <xs:element name="faxopcomplete" minOccurs="0"/>
   <xs:element name="faxpollstart" minOccurs="0"/>
  </xs:sequence>
 </xs:group>
 <xs:complexType name="hdrfooterType">
  <xs:choice>
   <xs:element name="format" type="xs:string" minOccurs="0"
               maxOccurs="unbounded"/>
  </xs:choice>
  <xs:attribute name="type" type="hdrfooter.datatype"/>
  <xs:attribute name="style" type="hdrfooterstyle.datatype"/>
 </xs:complexType>
 <xs:complexType name="formatType">
  <xs:simpleContent>
   <xs:extension base="xs:string">
    <xs:attribute name="style">
     <xs:simpleType>
      <xs:restriction base="xs:string">
       <xs:enumeration value="append"/>
       <xs:enumeration value="overlay"/>
       <xs:enumeration value="replace"/>
      </xs:restriction>



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     </xs:simpleType>
    </xs:attribute>
   </xs:extension>
  </xs:simpleContent>
 </xs:complexType>
 <xs:complexType name="rcvobjType">
  <xs:attribute name="objuri" type="xs:anyURI" use="required"/>
  <xs:attribute name="maxpages" type="xs:positiveInteger"/>
 </xs:complexType>
 <xs:complexType name="sendobjType">
  <xs:attribute name="objuri" type="xs:anyURI" use="required"/>
  <xs:attribute name="startpage" type="xs:positiveInteger"/>
  <xs:attribute name="pagecount" type="xs:positiveInteger"/>
 </xs:complexType>
 <xs:simpleType name="faxid.datatype">
  <xs:restriction base="xs:string">
   <xs:pattern value="[0-9+*- ]{20}"/>
  </xs:restriction>
 </xs:simpleType>
 <xs:simpleType name="faxspeed.datatype">
  <xs:restriction base="xs:string">
   <xs:enumeration value="2400"/>
   <xs:enumeration value="4800"/>
   <xs:enumeration value="7200"/>
   <xs:enumeration value="9600"/>
   <xs:enumeration value="12000"/>
   <xs:enumeration value="14400"/>
  </xs:restriction>
 </xs:simpleType>
 <xs:simpleType name="hdrfooter.datatype">
  <xs:restriction base="xs:string">
   <xs:enumeration value="header"/>
   <xs:enumeration value="footer"/>
   <xs:enumeration value="autohdr"/>
   <xs:enumeration value="nohdr"/>
  </xs:restriction>
 </xs:simpleType>
 <xs:simpleType name="hdrfooterstyle.datatype">
  <xs:restriction base="xs:string">
   <xs:enumeration value="append"/>
   <xs:enumeration value="overlay"/>
   <xs:enumeration value="replace"/>
  </xs:restriction>
 </xs:simpleType>
</xs:schema>






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16.4.  MSML Audit Packages

16.4.1.  msml-audit-core.xsd

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
           elementFormDefault="qualified"
           attributeFormDefault="unqualified">
 <xs:include schemaLocation="msml-core.xsd"/>
 <xs:include schemaLocation="msml-core-datatypes.xsd"/>
 <xs:include schemaLocation="msml-audit-core-datatypes.xsd"/>
</xs:schema>

16.4.2.  msml-audit-core-datatypes.xsd

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
           elementFormDefault="qualified"
           attributeFormDefault="unqualified">
 <xs:include schemaLocation="msml-core-datatypes.xsd"/>
 <xs:element name="audit" substitutionGroup="msmlRequest">
  <xs:complexType>
   <xs:complexContent>
    <xs:extension base="msmlRequestType">
     <xs:attribute name="queryid" type="auditQueryId.datatype"
                   use="required"/>
     <xs:attribute name="statelist" type="auditStateList.datatype"
                   use="optional"/>
    </xs:extension>
   </xs:complexContent>
  </xs:complexType>
 </xs:element>
 <xs:element name="auditresult" substitutionGroup="msmlResultComplex">
  <xs:complexType>
   <xs:complexContent>
    <xs:extension base="msmlResultComplexType">
    <xs:choice maxOccurs="unbounded">
     <xs:element ref="stateParameter"/>
     <xs:element ref="stateParameterSimple"/>
     </xs:choice>
     <xs:attribute name="targetid" type="independentID.datatype"
                   use="required"/>
    </xs:extension>
   </xs:complexContent>
  </xs:complexType>
 </xs:element>
 <xs:element name="stateParameter" type="stateParameterType"
             abstract="true"/>



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 <xs:element name="stateParameterSimple" type="stateParameterSimpleType"
             abstract="true"/>
 <xs:complexType name="stateParameterType"/>
 <xs:simpleType name="stateParameterSimpleType">
  <xs:restriction base="xs:string"/>
 </xs:simpleType>
 <xs:simpleType name="auditQueryId.datatype">
  <xs:restriction base="xs:string">
   <xs:pattern value="conf:[a-zA-Z0-9.:\-_]+"/>
   <xs:pattern value="conn:[a-zA-Z0-9.:\-_]+"/>
   <xs:pattern value="conf:\*"/>
   <xs:pattern value="conn:\*"/>
  </xs:restriction>
 </xs:simpleType>
 <xs:simpleType name="auditStateList.datatype">
  <xs:restriction base="xs:string"/>
 </xs:simpleType>
</xs:schema>

16.4.3.  msml-audit-conf.xsd

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
           elementFormDefault="qualified"
           attributeFormDefault="unqualified">
 <xs:include schemaLocation="msml-core.xsd"/>
 <xs:include schemaLocation="msml-core-datatypes.xsd"/>
 <xs:include schemaLocation="msml-audit-core-datatypes.xsd"/>
 <xs:include schemaLocation="msml-audit-dialog-datatypes.xsd"/>
 <xs:include schemaLocation="msml-audit-stream-datatypes.xsd"/>
 <xs:include schemaLocation="msml-audit-conf-datatypes.xsd"/>
</xs:schema>

16.4.4.  msml-audit-conf-datatypes.xsd

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
           elementFormDefault="qualified"
           attributeFormDefault="unqualified">
 <xs:include schemaLocation="msml-conf-core-datatypes.xsd"/>
 <xs:include schemaLocation="msml-audit-core-datatypes.xsd"/>
 <xs:element name="confconfig" substitutionGroup="stateParameter">
  <xs:complexType>
   <xs:complexContent>
    <xs:extension base="stateParameterType">
     <xs:sequence>
      <xs:element name="audiomix" type="audioMixType" minOccurs="0"
                  maxOccurs="unbounded"/>



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      <xs:element name="videolayout" type="videoLayoutType"
                  minOccurs="0" maxOccurs="unbounded"/>
      <xs:element name="controller" type="connID.datatype"
                  minOccurs="0"/>
     </xs:sequence>
     <xs:attribute name="deletewhen" use="optional" default="never">
      <xs:simpleType>
       <xs:restriction base="xs:string">
        <xs:enumeration value="nomedia"/>
        <xs:enumeration value="nocontrol"/>
        <xs:enumeration value="never"/>
       </xs:restriction>
      </xs:simpleType>
     </xs:attribute>
     <xs:attribute name="term" type="boolean.datatype" use="optional"
                   default="true"/>
    </xs:extension>
   </xs:complexContent>
  </xs:complexType>
 </xs:element>
</xs:schema>

16.4.5.  msml-audit-conn.xsd

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
           elementFormDefault="qualified"
           attributeFormDefault="unqualified">
 <xs:include schemaLocation="msml-core.xsd"/>
 <xs:include schemaLocation="msml-audit-core-datatypes.xsd"/>
 <xs:include schemaLocation="msml-audit-dialog-datatypes.xsd"/>
 <xs:include schemaLocation="msml-audit-stream-datatypes.xsd"/>
 <xs:include schemaLocation="msml-audit-conn-datatypes.xsd"/>
</xs:schema>

16.4.6.  msml-audit-conn-datatypes.xsd

<?xml version="1.0" encoding="UTF-8"?>
<xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
           elementFormDefault="qualified"
           attributeFormDefault="unqualified">
 <xs:include schemaLocation="msml-audit-core-datatypes.xsd"/>
 <xs:element name="sipdialog" substitutionGroup="stateParameter">
  <xs:complexType>
   <xs:complexContent>
    <xs:extension base="stateParameterType">
     <xs:sequence>
      <xs:element name="localseq" type="xs:integer" minOccurs="0"/>



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      <xs:element name="remoteseq" type="xs:int" minOccurs="0"/>
      <xs:element name="localuri" type="xs:string" minOccurs="0"/>
      <xs:element name="remoteuri" type="xs:string" minOccurs="0"/>
      <xs:element name="remotetarget" type="xs:string" minOccurs="0"/>
      <xs:element name="routeset" type="xs:string" minOccurs="0"/>
     </xs:sequence>
     <xs:attribute name="callid" type="xs:string" use="required"/>
     <xs:attribute name="localtag" type="xs:string" use="required"/>
     <xs:attribute name="remotetag" type="xs:string" use="required"/>
    </xs:extension>
   </xs:complexContent>
  </xs:complexType>
 </xs:element>
 <xs:element name="localsdp" type="stateParameterSimpleType"
             substitutionGroup="stateParameterSimple"/>
 <xs:element name="remotesdp" type="stateParameterSimpleType"
             substitutionGroup="stateParameterSimple"/>
</xs:schema>

16.4.7.  msml-audit-dialog-datatypes.xsd

   Audit Dialog functionality requires use of either the Audit Conf
   Package or the Audit Conn Package.

   <?xml version="1.0" encoding="UTF-8"?>
   <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
              elementFormDefault="qualified"
              attributeFormDefault="unqualified">
    <xs:include schemaLocation="msml-audit-core-datatypes.xsd"/>
    <xs:element name="dialog" substitutionGroup="stateParameter">
     <xs:complexType>
      <xs:complexContent>
       <xs:extension base="stateParameterType">
        <xs:sequence>
         <xs:element name="duration" type="xs:positiveInteger"
                     minOccurs="0"/>
         <xs:element name="primitive" minOccurs="0">
          <xs:simpleType>
           <xs:restriction base="xs:string">
            <xs:pattern value="play"/>
            <xs:pattern value="dtmf"/>
            <xs:pattern value="collect"/>
            <xs:pattern value="dtmfgen"/>
            <xs:pattern value="tonegen"/>
            <xs:pattern value="record"/>
            <xs:pattern value="none"/>
           </xs:restriction>
          </xs:simpleType>



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         </xs:element>
         <xs:element name="controller" type="connID.datatype"
                     minOccurs="0"/>
        </xs:sequence>
        <xs:attribute name="name" type="msmlInstanceID.datatype"
                      use="required"/>
        <xs:attribute name="src" type="xs:anyURI" use="optional"/>
        <xs:attribute name="type" type="dialogLanguage.datatype"
                      use="required"/>
       </xs:extension>
      </xs:complexContent>
     </xs:complexType>
    </xs:element>
   </xs:schema>

16.4.8.  msml-audit-stream-datatypes.xsd

   Audit Stream functionality requires use of either the Audit Conf
   Package or the Audit Conn Package.

   <?xml version="1.0" encoding="UTF-8"?>
   <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema"
              elementFormDefault="qualified"
              attributeFormDefault="unqualified">
    <xs:include schemaLocation="msml-audit-core-datatypes.xsd"/>
    <xs:element name="stream" substitutionGroup="stateParameter">
     <xs:complexType>
      <xs:complexContent>
       <xs:extension base="stateParameterType">
        <xs:all>
         <xs:element name="clamp" minOccurs="0">
          <xs:complexType>
           <xs:attribute name="dtmf" type="boolean.datatype"/>
           <xs:attribute name="tones" type="boolean.datatype"/>
          </xs:complexType>
         </xs:element>
         <xs:element name="gain" minOccurs="0">
          <xs:complexType>
           <xs:attribute name="amt" use="optional">
            <xs:simpleType>
             <xs:restriction base="xs:integer">
              <xs:minInclusive value="-96"/>
              <xs:maxInclusive value="96"/>
             </xs:restriction>
            </xs:simpleType>
           </xs:attribute>
           <xs:attribute name="agc" type="boolean.datatype"/>
           <xs:attribute name="tgtlvl" use="optional">



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            <xs:simpleType>
             <xs:restriction base="xs:nonPositiveInteger">
              <xs:minInclusive value="-40"/>
              <xs:maxInclusive value="0"/>
             </xs:restriction>
            </xs:simpleType>
           </xs:attribute>
           <xs:attribute name="maxgain" default="10">
            <xs:simpleType>
             <xs:restriction base="xs:nonNegativeInteger">
              <xs:minInclusive value="0"/>
              <xs:maxInclusive value="40"/>
             </xs:restriction>
            </xs:simpleType>
           </xs:attribute>
          </xs:complexType>
         </xs:element>
         <xs:element name="visual" minOccurs="0"/>
        </xs:all>
        <xs:attribute name="joinwith" type="independentID.datatype"
                      use="required"/>
        <xs:attribute name="media" use="required">
         <xs:simpleType>
          <xs:restriction base="xs:string">
           <xs:pattern value="audio"/>
           <xs:pattern value="video"/>
          </xs:restriction>
         </xs:simpleType>
        </xs:attribute>
        <xs:attribute name="dir" use="required">
         <xs:simpleType>
          <xs:restriction base="xs:string">
           <xs:pattern value="from"/>
           <xs:pattern value="to"/>
          </xs:restriction>
         </xs:simpleType>
        </xs:attribute>
        <xs:attribute name="compressed" type="boolean.datatype"/>
        <xs:attribute name="preferred" type="boolean.datatype"
                      default="false"/>
        <xs:attribute name="display" type="xs:string"/>
        <xs:attribute name="override" type="boolean.datatype"
                      default="false"/>
       </xs:extension>
      </xs:complexContent>
     </xs:complexType>
    </xs:element>
   </xs:schema>



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17.  Security Considerations

   MSML being an XML-based language, security considerations as defined
   by RFC 3023 [i2] are applicable.

   Media server interfaces driven using MSML are under the explicit
   control of a SIP application server.  SIP call legs are used to
   deliver XML-based MSML transactions to the media server.  The
   security and integrity of MSML transactions, whenever required,
   SHOULD use sips: and TLS for encryption and authentication of the SIP
   control channel used to carry MSML payloads.  Further information
   related to security, privacy, and integrity of MSML media types is
   described in the IANA Considerations section.

   Media streams, such as audio/video, MAY optionally be protected,
   encrypted/decrypted, and authenticated, utilizing Secure Real Time
   Protocol (SRTP), wherever media stream security is required.  Media
   negotiation establishes the required level of security and is
   initiated by the clients, which is outside the scope of the control
   interface specified by MSML.

18.  IANA Considerations

18.1.  IANA Registrations for 'application' MIME Media Type

   The following registrations have been made:

   Type Name: "application"

   Subtype names:

      'application/vnd.radisys.msml+xml',

      'application/vnd.radisys.moml+xml',

      'application/vnd.radisys.msml-conf+xml',

      'application/vnd.radisys.msml-dialog+xml',

      'application/vnd.radisys.msml-dialog-base+xml',

      'application/vnd.radisys.msml-dialog-group+xml',

      'application/vnd.radisys.msml-dialog-speech+xml',

      'application/vnd.radisys.msml-dialog-transform+xml',

      'application/vnd.radisys.msml-dialog-fax-detect+xml',



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      'application/vnd.radisys.msml-dialog-fax-sendrecv+xml',

      'application/vnd.radisys.msml-audit+xml',

      'application/vnd.radisys.msml-audit-conf+xml',

      'application/vnd.radisys.msml-audit-conn+xml',

      'application/vnd.radisys.msml-audit-dialog+xml',

      'application/vnd.radisys.msml-audit-stream+xml'

   Required parameters: none

   Optional parameters: charset

      charset semantics as specified in RFC 3023 [i2] for
      "application/xml" media type.

   Encoding considerations:

      As specified in RFC 3023 [i2].

   Security Considerations:

      Media types included in this section are XML based, and therefore
      security considerations as defined by RFC 3023 [i10] are
      applicable.

      These media types do not contain active or executable content as
      the content itself merely provides control of the underlying media
      streams.

      Secure exchange of content associated with these media types for
      purposes of authentication and privacy, whenever applicable, shall
      require the establishment of a secure control channel using sips:
      and TLS.

      Privacy and integrity of media content associated with these media
      types shall be considered when applications using these media
      types are exchanging personal information such as personal
      identification codes or conference access codes.  Whenever such
      content is deemed to require secure transport and authentication,
      a secure channel using sips: and TLS MUST be used, as these media
      types themselves provide no such inherent mechanisms for security.






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   Interoperability considerations:

      As specified in RFC 3023 [i2] and as specified within this
      document.

   Published specification: RFC 5707

   Intended applications for these media types:

      Multimedia Conferencing, Interactive Voice Response systems

   Additional information:

      Magic number(s): None

      File extension(s): None

      Macintosh file type code(s): None

   Person & email address to contact for further information:

      Adnan Saleem <adnan.saleem@radisys.com>

   Intended usage: COMMON

18.2.  IANA Registrations for 'text' MIME Media Type

   The following registrations are planned:

      'text/vnd.radisys.msml-basic-layout'

   Required parameters: none

   Optional parameters: charset

      charset semantics as specified in RFC 3023 [i2] for "text/xml"
      media type.

   Encoding considerations: As specified in RFC 3023 [i2].

   Security Considerations:

      Media types included in this section are XML based, and therefore
      security considerations as defined by RFC 3023 [i10] are
      applicable.






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      The media type defined in this section does not contain active or
      executable content.  The media type defines only a visual layout
      scheme of a video conference.  Establishment of active connections
      associated with the video conference are outside the scope of this
      media type.

      Since this media type only defines a visual layout scheme, with no
      reference or information about client connections or participants
      within the conference, privacy and integrity concerns are not
      applicable to this media type.

   Interoperability considerations:

      As specified in RFC 3023 [i2] and as specified within this
      document.

   Published specification: RFC 5707

   Intended applications for these media types:

      Multimedia Conferencing, Interactive Voice Response systems

   Additional information:

      Magic number(s): None

      File extension(s): None

      Macintosh file type code(s): None

   Person & email address to contact for further information:

      Adnan Saleem <adnan.saleem@radisys.com>

   Intended usage: COMMON

18.3.  URN Sub-Namespace Registration

   The namespace URI for elements defined within this specification is a
   URN [i8].  It uses the namespace identifier 'ietf' defined by [i9]
   and extended by RFC 3688 [i10].

   The following registrations of URN Sub-Namespaces are planned:

   XML namespace: urn:ietf:params:xml:ns:msml






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   XML:

   BEGIN

   <?xml version="1.0"?>

   <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML Basic 1.0//EN"

   "http://www.w3.org/TR/xhtml-basic/xhtml-basic10.dtd">

   <html xmlns="http://www.w3.org/1999/xhtml">

     <head>

         <meta http-equiv="content-type"

               content="text/html;charset=iso-8859-1"/>

         <title>Media Server Markup Language Namespace</title>

     </head>

     <body>

        <h1>Namespace for Media Server Markup Language</h1>

        <h2>urn:ietf:params:xml:ns:msml</h2>

        <p>See MSML <a
       href="http://www.rfc-editor.org/rfc/rfc5707.txt">RFC 5707</a></p>

     </body>

   </html>

   END

18.4.  XML Schema Registration

   This section registers an XML schema per the procedures in [i10].

   URI: urn:ietf:params:xml:schema:msml

   Registrant Contact:

      Adnan Saleem (adnan.saleem@radisys.com) and authors listed
      within this document.




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   The XML for this schema can be found as the sole content of Section
   16.

19.  References

19.1.  Normative References

   [n1]  Rosenberg, J., Schulzrinne, H., Camarillo, G., Johnston, A.,
         Peterson, J., Sparks, R., Handley, M., and E. Schooler, "SIP:
         Session Initiation Protocol", RFC 3261, June 2002.

   [n2]  Bray, T., Paoli, J., Sperberg-McQueen, C., and E. Maler,
         "Extensible Markup Language (XML) 1.0 (Second Edition)," W3C
         First Edition REC-xml-20001006, October 2000.

   [n3]  World Wide Web Consortium, "Speech Recognition Grammar
         Specification Version 1.0" (SRGS), W3C Candidate
         Recommendation, March 16, 2004

   [n4]  World Wide Web Consortium, "Natural Language Semantics Markup
         Language (NLSML) for the Speech Interface Framework", W3C
         Working Draft 20, November 2000.

   [n5]  World Wide Web Consortium, "Voice Extensible Markup Language
         (VoiceXML) Version 2.0, W3C Candidate Recommendation, March 16,
         2004.

   [n6]  Berners-Lee, T., Fielding, R., and L. Masinter, "Uniform
         Resource Identifier (URI): Generic Syntax", STD 66, RFC 3986,
         January 2005.

   [n7]  Burger, E., Ed., Van Dyke, J., and A. Spitzer, "Basic Network
         Media Services with SIP", RFC 4240, December 2005.

   [n8]  Levinson, E., "Content-ID and Message-ID Uniform Resource
         Locators", RFC 2392, August 1998.

   [n9]  Handley, M., Jacobson, V., and C. Perkins, "SDP: Session
         Description Protocol", RFC 4566, July 2006.

   [n10] Bos, B., Lie, H., Tantek, C., and Hickson, I., "Cascading Style
         Sheets, level 2 (CSS2) Specification," W3C REC CR-CSS21-, July
         2007.

   [n11] Burnett, D., Walker, M., and Hunt, A., "Speech Synthesis Markup
         Language (SSML) Version 1.0", W3C Recommendation, 7 September
         2004.




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19.2.  Informative References

   [i1]  Rosenberg, J., Schulzrinne, H., and P. Kyzivat, "Indicating
         User Agent Capabilities in the Session Initiation Protocol
         (SIP)", RFC 3840, August 2004.

   [i2]  Murata, M., St. Laurent, S., and D. Kohn, "XML Media Types",
         RFC 3023, January 2001.

   [i3]  Schulzrinne, H., Casner, S., Frederick, R., and V. Jacobson,
         "RTP: A Transport Protocol for Real-Time Applications", STD 64,
         RFC 3550, July 2003.

   [i4]  Rosenberg, J., Peterson, J., Schulzrinne, H., and G. Camarillo,
         "Best Current Practices for Third Party Call Control (3pcc) in
         the Session Initiation Protocol (SIP)", BCP 85, RFC 3725, April
         2004.

   [i5]  Donovan, S., "The SIP INFO Method", RFC 2976, October 2000.

   [i6]  Ossenbruggen, J., Rutledge, L., Saccocio, B., Schmitz, P.,
         Kate, W., Ayars, J., Bulterman, D., Cohen, A., Day, K., Hodge,
         E., Hoschka, P., Hyche, E., Jourdan, M., Kubota, K., Lanphier,
         R., Laya'da, N., Michel, T., and D. Newman, "Synchronized
         Multimedia Integration Language (SMIL 2.0) Specification," W3C
         REC REC-smil2-20050107, January 2005.

   [i7]  Freed, N. and N. Borenstein, "Multipurpose Internet Mail
         Extensions (MIME) Part Two: Media Types", RFC 2046, November
         1996.

   [i8]  Moats, R., "URN Syntax", RFC 2141, May 1997.

   [i9]  Moats, R., "A URN Namespace for IETF Documents", RFC 2648,
         August 1999.

   [i10] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
         January 2004.

   [i11] Boulton, C., Melanchuk, T., McGlashan, S., and A. Shiratzky, "A
         Control Framework for the Session Initiation Protocol (SIP)",
         Work in Progress, February 2007.









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Acknowledgments

   Sergiu Stambolian of RadiSys provided key insights, both theoretic
   and through development experience, on several versions of the
   document.

   Stephen Buko and George Raskulinec of Intel made numerous valuable
   contributions towards enhancements of multimedia playback and record
   operations.  Gene Shtirmer of Intel provided review feedback on
   several revisions and feature enhancement suggestions.

   David Asher of NMS Communications provided valuable insights towards
   creation of standard profiles and a modularization scheme based on
   packages for better interoperability.

   Gilles Compienne of Ubiquity Software has provided feedback on
   several earlier versions of this document.

   Chris Boulton and Ben Smith, both of Ubiquity, and Michael Rice of
   VocalData helped clarify several issues, while Bruce Walsh and Kevin
   Fitzgerald, both of Spectel/Avaya, provided important feedback.
   Cliff Schornak of Commetrex significantly contributed to the
   facsimile work.  Peter Danielsen of Lucent has contributed thoughtful
   and detailed reviews for several earlier versions of the document.



























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Authors' Addresses

   Adnan Saleem
   RadiSys
   4190 Still Creek Drive, Suite 300
   Burnaby, BC, V5C 6C6
   Canada

   Phone: +1 604 918 6376
   EMail : adnan.saleem@radisys.com


   Yong Xin
   RadiSys
   4190 Still Creek Drive, Suite 300
   Burnaby, BC, V5C 6C6
   Canada

   Phone: +1 604 918 6383
   EMail: yong.xin@radiSys.com


   Garland Sharratt
   Consultant
   Vancouver, BC
   Canada

   EMail: garland.sharratt@gmail.com























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