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diff --git a/doc/rfc/rfc6917.txt b/doc/rfc/rfc6917.txt new file mode 100644 index 0000000..1752a0a --- /dev/null +++ b/doc/rfc/rfc6917.txt @@ -0,0 +1,7619 @@ + + + + + + +Internet Engineering Task Force (IETF) C. Boulton +Request for Comments: 6917 NS-Technologies +Category: Standards Track L. Miniero +ISSN: 2070-1721 Meetecho + G. Munson + AT&T + April 2013 + + + Media Resource Brokering + +Abstract + + The MediaCtrl working group in the IETF has proposed an architecture + for controlling media services. The Session Initiation Protocol + (SIP) is used as the signaling protocol that provides many inherent + capabilities for message routing. In addition to such signaling + properties, a need exists for intelligent, application-level media + service selection based on non-static signaling properties. This is + especially true when considered in conjunction with deployment + architectures that include 1:M and M:N combinations of Application + Servers and Media Servers. This document introduces a Media Resource + Broker (MRB) entity, which manages the availability of Media Servers + and the media resource demands of Application Servers. The document + includes potential deployment options for an MRB and appropriate + interfaces to Application Servers and Media Servers. + +Status of This Memo + + This is an Internet Standards Track document. + + This document is a product of the Internet Engineering Task Force + (IETF). It represents the consensus of the IETF community. It has + received public review and has been approved for publication by the + Internet Engineering Steering Group (IESG). Further information on + Internet Standards is available in 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/rfc6917. + + + + + + + + + + + +Boulton, et al. Standards Track [Page 1] + +RFC 6917 Media Resource Brokering April 2013 + + +Copyright Notice + + Copyright (c) 2013 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. Code Components extracted from this document must + include Simplified BSD License text as described in Section 4.e of + the Trust Legal Provisions and are provided without warranty as + described in the Simplified BSD License. + +Table of Contents + + 1. Introduction ....................................................3 + 2. Conventions and Terminology .....................................6 + 3. Problem Discussion ..............................................6 + 4. Deployment Scenario Options .....................................7 + 4.1. Query MRB ..................................................8 + 4.1.1. Hybrid Query MRB ....................................9 + 4.2. In-Line MRB ...............................................11 + 5. MRB Interface Definitions ......................................12 + 5.1. Media Server Resource Publish Interface ...................12 + 5.1.1. Control Package Definition .........................13 + 5.1.2. Element Definitions ................................15 + 5.1.3. <mrbrequest> .......................................15 + 5.1.4. <mrbresponse> ......................................17 + 5.1.5. <mrbnotification> ..................................19 + 5.2. Media Service Resource Consumer Interface .................30 + 5.2.1. Query Mode/HTTP Consumer Interface Usage ...........31 + 5.2.2. In-Line Aware Mode/SIP Consumer Interface Usage ....32 + 5.2.3. Consumer Interface Lease Mechanism .................35 + 5.2.4. <mrbconsumer> ......................................38 + 5.2.5. Media Service Resource Request .....................39 + 5.2.6. Media Service Resource Response ....................51 + 5.3. In-Line Unaware MRB Interface .............................54 + 6. MRB Acting as a B2BUA ..........................................54 + 7. Multimodal MRB Implementations .................................55 + 8. Relative Merits of Query Mode, IAMM, and IUMM ..................56 + 9. Examples .......................................................58 + 9.1. Publish Example ...........................................58 + 9.2. Consumer Examples .........................................64 + 9.2.1. Query Example ......................................64 + 9.2.2. IAMM Examples ......................................68 + 10. Media Service Resource Publisher Interface XML Schema .........83 + + + +Boulton, et al. Standards Track [Page 2] + +RFC 6917 Media Resource Brokering April 2013 + + + 11. Media Service Resource Consumer Interface XML Schema .........106 + 12. Security Considerations ......................................127 + 13. IANA Considerations ..........................................130 + 13.1. Media Control Channel Framework Package Registration ....130 + 13.2. application/mrb-publish+xml Media Type ..................130 + 13.3. application/mrb-consumer+xml Media Type .................131 + 13.4. URN Sub-Namespace Registration for mrb-publish ..........132 + 13.5. URN Sub-Namespace Registration for mrb-consumer .........132 + 13.6. XML Schema Registration for mrb-publish .................132 + 13.7. XML Schema Registration for mrb-consumer ................133 + 14. Acknowledgements .............................................133 + 15. References ...................................................133 + 15.1. Normative References ....................................133 + 15.2. Informative References ..................................135 + +1. Introduction + + As IP-based multimedia infrastructures mature, the complexity and + demands from deployments increase. Such complexity will result in a + wide variety of capabilities from a range of vendors that should all + be interoperable using the architecture and protocols produced by the + MediaCtrl working group. It should be possible for a controlling + entity to be assisted in Media Server selection so that the most + appropriate resource is selected for a particular operation. The + importance increases when one introduces a flexible level of + deployment scenarios, as specified in RFC 5167 [RFC5167] and RFC 5567 + [RFC5567]. These documents make statements like "it should be + possible to have a many-to-many relationship between Application + Servers and Media Servers that use this protocol". This leads to the + following deployment architectures being possible when considering + media resources, to provide what can be effectively described as + media resource brokering. + + The simplest deployment view is illustrated in Figure 1. + + +---+-----+---+ +---+-----+---+ + | Application | | Media | + | Server |<-------MS Control------>| Server | + +-------------+ +-------------+ + + Figure 1: Basic Architecture + + This simply involves a single Application Server and Media Server. + Expanding on this view, it is also possible for an Application Server + to control multiple (greater than 1) Media Server instances at any + one time. This deployment view is illustrated in Figure 2. + Typically, such architectures are associated with application logic + that requires high-demand media services. It is more than possible + + + +Boulton, et al. Standards Track [Page 3] + +RFC 6917 Media Resource Brokering April 2013 + + + that each Media Server possesses a different media capability set. + Media Servers may offer different media services as specified in the + MediaCtrl architecture document [RFC5567]. A Media Server may have + similar media functionality but may have different capacity or media + codec support. + + +---+-----+---+ + | Media | + +----->| Server | + | +-------------+ + | + +---+-----+---+ | +---+-----+---+ + | Application | | | Media | + | Server |<--MS Control-----+----->| Server | + +-------------+ | +-------------+ + | + | +---+-----+---+ + +----->| Media | + | Server | + +-------------+ + + Figure 2: Multiple Media Servers + + Figure 3 conveys the opposite view to that in Figure 2. In this + model, there are a number of (greater than 1) Application Servers, + possibly supporting dissimilar applications, controlling a single + Media Server. Typically, such architectures are associated with + application logic that requires low-demand media services. + + +---+-----+---+ + | Application | + | Server |<-----+ + +-------------+ | + | + +---+-----+---+ | +---+-----+---+ + | Application | | | Media | + | Server |<-----+-----MS Control-->| Server | + +-------------+ | +-------------+ + | + +---+-----+---+ | + | Application | | + | Server |<-----+ + +-------------+ + + Figure 3: Multiple Application Servers + + + + + + +Boulton, et al. Standards Track [Page 4] + +RFC 6917 Media Resource Brokering April 2013 + + + The final deployment view is the most complex (Figure 4). In this + model (M:N), there exist any number of Application Servers and any + number of Media Servers. It is again possible in this model that + Media Servers might not be homogeneous, and they might have different + capability sets and capacities. + + +---+-----+---+ +---+-----+---+ + | Application | | Media | + | Server |<-----+ +---->| Server | + +-------------+ | | +-------------+ + | | + +---+-----+---+ | | +---+-----+---+ + | Application | | | | Media | + | Server |<-----+-MS Control-+---->| Server | + +-------------+ | | +-------------+ + | | + +---+-----+---+ | | +---+-----+---+ + | Application | | +---->| Media | + | Server |<-----+ | Server | + +-------------+ +---+-----+---+ + + Figure 4: Many-to-Many Architecture + + The remaining sections in this specification will focus on a new + entity called a Media Resource Broker (MRB), which can be utilized in + the deployment architectures described previously in this section. + The MRB entity provides the ability to obtain media resource + information and appropriately allocate (broker) on behalf of client + applications. + + The high-level deployment options discussed in this section rely on + network architecture and policy to prohibit inappropriate use. Such + policies are out of scope for this document. + + This document will take a look at the specific problem areas related + to such deployment architectures. It is recognized that the + solutions proposed in this document should be equally adaptable to + all of the previously described deployment models. It is also + recognized that the solution is far more relevant to some of the + previously discussed deployment models and can almost be viewed as + redundant on others. + + + + + + + + + + +Boulton, et al. Standards Track [Page 5] + +RFC 6917 Media Resource Brokering April 2013 + + +2. Conventions and Terminology + + The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", + "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this + document are to be interpreted as described in RFC 2119 [RFC2119]. + + This document inherits terminology proposed in RFC 5567 [RFC5567] and + in "Media Control Channel Framework" [RFC6230]. In addition, the + following terms are defined for use in this document and for use in + the context of the MediaCtrl working group in the IETF: + + Media Resource Broker (MRB): A logical entity that is responsible + for both collection of appropriate published Media Server (MS) + information and selecting appropriate Media Server resources on + behalf of consuming entities. + + Query MRB: An instantiation of an MRB (see previous definition) that + provides an interface for an Application Server to retrieve the + address of an appropriate Media Server. The result returned to + the Application Server can be influenced by information contained + in the query request. + + In-line MRB: An instantiation of an MRB (see previous definition) + that directly receives requests on the signaling path. There is + no separate query. + + CFW: Media Control Channel Framework, as specified in [RFC6230]. + + Within the context of In-line MRBs, additional terms are defined: + + In-line Aware MRB Mode (IAMM): Defined in Section 5.2.2.1. + + In-line Unaware MRB Mode (IUMM): Defined in Section 5.3. + + The document will often specify when a specific identifier in a + protocol message needs to be unique. Unless stated otherwise, such + uniqueness will always be within the scope of the Media Servers + controlled by the same MRB. The interaction between different MRB + instances, e.g., the partitioning of a logical MRB, is out of scope + for this document. + +3. Problem Discussion + + As discussed in Section 1, a goal of the MediaCtrl working group is + to produce a solution that will service a wide variety of deployment + architectures. Such architectures range from the simplest 1:1 + relationship between Media Servers and Application Servers to + potentially linearly scaling 1:M, M:1, and M:N deployments. + + + +Boulton, et al. Standards Track [Page 6] + +RFC 6917 Media Resource Brokering April 2013 + + + Managing such deployments is itself non-trivial for the proposed + solution until an additional number of factors that increase + complexity are included in the equation. As Media Servers evolve, it + must be taken into consideration that, where many can exist in a + deployment, they may not have been produced by the same vendor and + may not have the same capability set. It should be possible for an + Application Server that exists in a deployment to select a media + service based on a common, appropriate capability set. In + conjunction with capabilities, it is also important to take available + resources into consideration. The ability to select an appropriate + media service function is an extremely useful feature but becomes + even more powerful when considered with available resources for + servicing a request. + + In conclusion, the intention is to create a toolkit that allows + MediaCtrl deployments to effectively utilize the available media + resources. It should be noted that in the simplest deployments where + only a single Media Server exists, an MRB function is probably not + required. Only a single capability set exists, and resource + availability can be handled using the appropriate underlying + signaling, e.g., SIP response. This document does not prohibit such + uses of an MRB; it simply provides the tools for various entities to + interact where appropriate. It is also worth noting that the + functions specified in this document aim to provide a 'best effort' + view of media resources at the time of request for initial Media + Server routing decisions. Any dramatic change in media capabilities + or capacity after a request has taken place should be handled by the + underlying protocol. + + It should be noted that there may be additional information that is + desirable for the MRB to have for purposes of selecting a Media + Server resource, such as resource allocation rules across different + applications, planned or unplanned downtime of Media Server + resources, the planned addition of future Media Server resources, or + Media Server resource capacity models. How the MRB acquires such + information is outside the scope of this document. The specific + techniques used for selecting an appropriate media resource by an MRB + is also outside the scope of this document. + +4. Deployment Scenario Options + + Research into media resource brokering concluded that a couple of + high-level models provided an appropriate level of flexibility. The + general principles of "in-line" and "query" MRB concepts are + discussed in the rest of this section. It should be noted that while + the interfaces are different, they both use common underlying + mechanisms defined in this specification. + + + + +Boulton, et al. Standards Track [Page 7] + +RFC 6917 Media Resource Brokering April 2013 + + +4.1. Query MRB + + The "Query" model for MRB interactions provides the ability for a + client of media services (for example, an Application Server) to + "ask" an MRB for an appropriate Media Server, as illustrated in + Figure 5. + + +---+-----+---+ + +------------>| MRB |<----------+----<-----+---+ + | +-------------+ (1)| | | + | | | | + |(2) +---+--+--+---+ | | + | | Media | | | + | +---->| Server | | | + | | +-------------+ | | + | | (1)| | + +---+--+--+---+ | +---+-----+---+ | | + | Application | | | Media | | | + | Server |<-----+-MS Control-+---->| Server |->-+ | + +-------------+ (3) | +-------------+ | + | | + | +---+-----+---+ (1)| + +---->| Media | | + | Server |--->---+ + +---+-----+---+ + + Figure 5: Query MRB + + In this deployment, the Media Servers use the Media Server Resource + Publish interface, as discussed in Section 5.1, to convey capability + sets as well as resource information. This is depicted by (1) in + Figure 5. It is then the MRB's responsibility to accumulate all + appropriate information relating to media services in the logical + deployment cluster. The Application Server (or other media services + client) is then able to query the MRB for an appropriate resource (as + identified by (2) in Figure 5). Such a query would carry specific + information related to the media service required and enable the MRB + to provide increased accuracy in its response. This particular + interface is discussed in "Media Service Resource Consumer Interface" + (Section 5.2). The Application Server is then able to direct control + commands (for example, create a conference) and media dialogs to the + appropriate Media Server, as shown by (3) in Figure 5. Additionally, + with Query mode, the MRB is not directly in the signaling path + between the Application Server and the selected Media Server + resource. + + + + + + +Boulton, et al. Standards Track [Page 8] + +RFC 6917 Media Resource Brokering April 2013 + + +4.1.1. Hybrid Query MRB + + As mentioned previously, it is the intention that a toolkit is + provided for MRB functionality within a MediaCtrl architecture. It + is expected that in specific deployment scenarios the role of the MRB + might be co-hosted as a hybrid logical entity with an Application + Server, as shown in Figure 6. + + +------------<----------------<---------+----<-----+---+ + | (1) | | | + | | | | + | +---+--+--+---+ | | + | | Media | | | + V +---->| Server | | | + +------+------+ | +-------------+ | | + | MRB | | | | + +---+--+--+---+ | +---+-----+---+ | | + | Application | | | Media | | | + | Server |<-----+-MS Control-+---->| Server |->-+ | + +-------------+ | +-------------+ | + | | + | +---+-----+---+ | + +---->| Media | | + | Server |--->---+ + +---+-----+---+ + + Figure 6: Hybrid Query MRB - Application Server Hosted + + This diagram is identical to that in Figure 5 with the exception that + the MRB is now hosted on the Application Server. The Media Server + Publish interface is still being used to accumulate resource + information at the MRB, but as it is co-hosted on the Application + Server, the Media Server Consumer interface has collapsed. It might + still exist within the Application Server/MRB interaction, but this + is an implementation issue. This type of deployment suits a single + Application Server environment, but it should be noted that a Media + Server Consumer interface could then be offered from the hybrid if + required. + + + + + + + + + + + + + +Boulton, et al. Standards Track [Page 9] + +RFC 6917 Media Resource Brokering April 2013 + + + In a similar manner, the Media Server could also act as a hybrid for + the deployment cluster, as illustrated in Figure 7. + + (1) +---+-----+---+ + +---+---+------------->---------------->----------->| MRB | + | | | +---+--+--+---+ +---+-----+---+ + | | +-<-| Application | | Media | + | | | Server |<--+-MS Control-+------->| Server | + | | +-------------+ | +-------------+ + | | | + | | +---+--+--+---+ | + | +---<---| Application | | + | | Server |<--+-MS Control-+--+ + | +-------------+ | + | | + | +---+--+--+---+ | + +---<-------| Application | | + | Server |<--+-MS Control-+--+ + +-------------+ + + Figure 7: Hybrid Query MRB - MS Hosted + + In this example, the MRB has collapsed and is co-hosted by the Media + Server. The Media Server Consumer interface is still available to + the Application Servers (1) to query Media Server resources. The + Media Server Publish interface has collapsed onto the Media Server. + It might still exist within the Media Server/MRB interaction, but + this is an implementation issue. This type of deployment suits a + single Media Server environment, but it should be noted that a Media + Server Publish interface could then be offered from the hybrid if + required. A typical use case scenario for such a topology would be a + single Media Server representing a pool of MSs in a cluster. In this + case, the MRB would actually be handling a cluster of Media Servers, + rather than one. + + + + + + + + + + + + + + + + + +Boulton, et al. Standards Track [Page 10] + +RFC 6917 Media Resource Brokering April 2013 + + +4.2. In-Line MRB + + The "In-line" MRB is architecturally different from the "Query" model + discussed in the previous section. The concept of a separate query + disappears. The client of the MRB simply uses the media resource + control and media dialog signaling to involve the MRB. This type of + deployment is illustrated in Figure 8. + + +-------<----------+----<-------+---+ + | | (1) | | + | | | | + | +---+--+--+---+ | | + | | Media | | | + | +------>| Server | | | + | |(3) +-------------+ | | + | | (1)| | + +---+--+--+---+ | | +---+-----+---+ | | + | Application | (2) +---+--V--+---+ (3) | Media | | | + | Server |----->| MRB |----->| Server |->-+ | + +-------------+ +---+-----+---+ +-------------+ | + | | + | (3) +---+-----+---+ (1)| + +------>| Media | | + | Server |--->---+ + +---+-----+---+ + + Figure 8: In-Line MRB + + The Media Servers still use the Media Server Publish interface to + convey capabilities and resources to the MRB, as illustrated by (1). + The Media Server Control Channels (and media dialogs as well, if + required) are sent to the MRB (2), which then selects an appropriate + Media Server (3) and remains in the signaling path between the + Application Server and the Media Server resources. + + The In-line MRB can be split into two distinct logical roles that can + be applied on a per-request basis. They are: + + In-line Unaware MRB Mode (IUMM): Allows an MRB to act on behalf of + clients requiring media services who are not aware of an MRB or + its operation. In this case, the Application Server does not + provide explicit information on the kind of Media Server resource + it needs (as in Section 5.2), and the MRB is left to deduce it by + potentially inspecting other information in the request from the + Application Server (for example, Session Description Protocol + (SDP) content, or address of the requesting Application Server, or + additional Request-URI parameters as per RFC 4240 [RFC4240]). + + + + +Boulton, et al. Standards Track [Page 11] + +RFC 6917 Media Resource Brokering April 2013 + + + In-line Aware MRB Mode (IAMM): Allows an MRB to act on behalf of + clients requiring media services who are aware of an MRB and its + operation. In particular, it allows the Application Server to + explicitly convey matching characteristics to those provided by + Media Servers, as does the Query MRB mode (as in Section 5.2). + + In either of the previously described roles, signaling as specified + by the Media Control Channel Framework ([RFC6230]) would be involved, + and the MRB would deduce that the selected Media Server resources are + no longer needed when the Application Server or Media Server + terminates the corresponding SIP dialog. The two modes are discussed + in more detail in Section 5.3. + +5. MRB Interface Definitions + + The intention of this specification is to provide a toolkit for a + variety of deployment architectures where media resource brokering + can take place. Two main interfaces are required to support the + differing requirements. The two interfaces are described in the + remainder of this section and have been named the Media Server + Resource Publish and Media Server Resource Consumer interfaces. + + It is beyond the scope of this document to define exactly how to + construct an MRB using the interfaces described. It is, however, + important that the two interfaces are complimentary so that + development of appropriate MRB functionality is supported. + +5.1. Media Server Resource Publish Interface + + The Media Server Resource Publish interface is responsible for + providing an MRB with appropriate Media Server resource information. + As such, this interface is assumed to provide both general and + specific details related to Media Server resources. This information + needs to be conveyed using an industry standard mechanism to provide + increased levels of adoption and interoperability. A Control Package + for the Media Control Channel Framework will be specified to fulfill + this interface requirement. It provides an establishment and + monitoring mechanism to enable a Media Server to report appropriate + statistics to an MRB. The Publish interface is used with both the + Query mode and In-line mode of MRB operation. + + As already discussed in Section 1, the MRB view of Media Server + resource availability will in reality be approximate -- i.e., partial + and imperfect. The MRB Publish interface does not provide an + exhaustive view of current Media Server resource consumption; the + Media Server may in some cases provide a best-effort computed view of + resource consumption parameters conveyed in the Publish interface + (e.g., Digital Signal Processors (DSPs) with a fixed number of + + + +Boulton, et al. Standards Track [Page 12] + +RFC 6917 Media Resource Brokering April 2013 + + + streams versus Graphics Processing Units (GPUs) with CPU + availability). Media resource information may only be reported + periodically over the Publish interface to an MRB. + + It is also worth noting that while the scope of the MRB is in + providing interested Application Servers with the available + resources, the MRB also allows for the retrieval of information about + consumed resources. While this is of course a relevant piece of + information (e.g., for monitoring purposes), such functionality + inevitably raises security considerations, and implementations should + take this into account. See Section 12 for more details. + + The MRB Publish interface uses the Media Control Channel Framework + ([RFC6230]) as the basis for interaction between a Media Server and + an MRB. The Media Control Channel Framework uses an extension + mechanism to allow specific usages that are known as Control + Packages. Section 5.1.1 defines the Control Package that MUST be + implemented by any Media Server wanting to interact with an MRB + entity. + +5.1.1. Control Package Definition + + This section fulfills the requirement for information that must be + specified during the definition of a Control Framework package, as + detailed in Section 8 of [RFC6230]. + +5.1.1.1. Control Package Name + + The Media Channel Control Framework requires a Control Package + definition to specify and register a unique name and version. + + The name and version of this Control Package is "mrb-publish/1.0". + +5.1.1.2. Framework Message Usage + + The MRB Publish interface allows a Media Server to convey available + capabilities and resources to an MRB entity. + + This package defines XML elements in Section 5.1.2 and provides an + XML schema in Section 10. + + The XML elements in this package are split into requests, responses, + and event notifications. Requests are carried in CONTROL message + bodies; the <mrbrequest> element is defined as a package request. + This request can be used for creating new subscriptions and updating/ + removing existing subscriptions. Event notifications are also + carried in CONTROL message bodies; the <mrbnotification> element is + + + + +Boulton, et al. Standards Track [Page 13] + +RFC 6917 Media Resource Brokering April 2013 + + + defined for package event notifications. Responses are carried + either in REPORT message or Control Framework 200 response bodies; + the <mrbresponse> element is defined as a package-level response. + + Note that package responses are different from framework response + codes. Framework error response codes (see Section 7 of [RFC6230]) + are used when the request or event notification is invalid; for + example, a request has invalid XML (400) or is not understood (500). + Package-level responses are carried in framework 200 response or + REPORT message bodies. This package's response codes are defined in + Section 5.1.4. + +5.1.1.3. Common XML Support + + The Media Control Channel Framework [RFC6230] requires a Control + Package definition to specify if the attributes for media dialog or + conference references are required. + + The Publish interface defined in Section 10 does import and make use + of the common XML schema defined in the Media Control Channel + Framework. + + The Consumer interface defined in Section 11 does import and make use + of the common XML schema defined in the Media Control Channel + Framework. + +5.1.1.4. CONTROL Message Body + + A valid CONTROL message body MUST conform to the schema defined in + Section 10 and described in Section 5.1.2. XML messages appearing in + CONTROL messages MUST contain either an <mrbrequest> or + <mrbnotification> element. + +5.1.1.5. REPORT Message Body + + A valid REPORT message body MUST conform to the schema defined in + Section 10 and described in Section 5.1.2. XML messages appearing in + REPORT messages MUST contain an <mrbresponse> element. + +5.1.1.6. Audit + + The 'mrb-publish/1.0' Media Control Channel Framework package does + not require any additional auditing capability. + + + + + + + + +Boulton, et al. Standards Track [Page 14] + +RFC 6917 Media Resource Brokering April 2013 + + +5.1.2. Element Definitions + + This section defines the XML elements for the Publish interface Media + Control Channel package defined in Section 5.1. The formal XML + schema definition for the Publish interface can be found in + Section 10. + + The root element is <mrbpublish>. All other XML elements (requests, + responses, notifications) are contained within it. The MRB Publish + interface request element is detailed in Section 5.1.3. The MRB + Publish interface notification element is detailed in Section 5.1.5. + The MRB Publish interface response element is detailed in + Section 5.1.4. + + The <mrbpublish> element has the following attributes: + + version: a token specifying the mrb-publish package version. The + value is fixed as '1.0' for this version of the package. The + attribute MUST be present. + + The <mrbpublish> element has the following child elements, and there + MUST NOT be more than one such child element in any <mrbpublish> + message: + + <mrbrequest> for sending an MRB request. See Section 5.1.3. + + <mrbresponse> for sending an MRB response. See Section 5.1.4. + + <mrbnotification> for sending an MRB notification. See + Section 5.1.5. + +5.1.3. <mrbrequest> + + This section defines the <mrbrequest> element used to initiate + requests from an MRB to a Media Server. The element describes + information relevant for the interrogation of a Media Server. + + The <mrbrequest> element has no defined attributes. + + The <mrbrequest> element has the following child element: + + <subscription> for initiating a subscription to a Media Server + from an MRB. See Section 5.1.3.1. + + + + + + + + +Boulton, et al. Standards Track [Page 15] + +RFC 6917 Media Resource Brokering April 2013 + + +5.1.3.1. <subscription> + + The <subscription> element is included in a request from an MRB to a + Media Server to provide the details relating to the configuration of + updates (known as a subscription session). This element can be used + either to request a new subscription or to update an existing one + (e.g., to change the frequency of the updates), and to remove ongoing + subscriptions as well (e.g., to stop an indefinite update). The MRB + will inform the Media Server regarding how long it wishes to receive + updates and the frequency that updates should be sent. Updates + related to the subscription are sent using the <mrbnotification> + element. + + The <subscription> element has the following attributes: + + id: Indicates a unique token representing the subscription session + between the MRB and the Media Server. The attribute MUST be + present. + + seqnumber: Indicates a sequence number to be used in conjunction + with the subscription session ID to identify a specific + subscription command. The first subscription MUST contain a + non-zero number 'seqnumber', and subsequent subscriptions MUST + contain a higher number than the previous 'seqnumber' value. If a + subsequent 'seqnumber' is not higher, a 405 response code is + generated as per Section 5.1.4. The attribute MUST be present. + + action: Provides the operation that should be carried out on the + subscription: + + * The value of 'create' instructs the Media Server to attempt to + set up a new subscription. + + * The value of 'update' instructs the Media Server to attempt to + update an existing subscription. + + * The value of 'remove' instructs the Media Server to attempt to + remove an existing subscription and consequently stop any + ongoing related notification. + + The attribute MUST be present. + + + + + + + + + + +Boulton, et al. Standards Track [Page 16] + +RFC 6917 Media Resource Brokering April 2013 + + + The <subscription> element has zero or more of the following child + elements: + + <expires>: Provides the amount of time in seconds that a + subscription should be installed for notifications at the Media + Server. Once the amount of time has passed, the subscription + expires, and the MRB has to subscribe again if it is still + interested in receiving notifications from the Media Server. The + element MAY be present. + + <minfrequency>: Provides the minimum frequency in seconds that the + MRB wishes to receive notifications from the Media Server. The + element MAY be present. + + <maxfrequency>: Provides the maximum frequency in seconds that the + MRB wishes to receive notifications from the Media Server. The + element MAY be present. + + Please note that these three optional pieces of information provided + by the MRB only act as a suggestion: the Media Server MAY change the + proposed values if it considers the suggestions unacceptable (e.g., + if the MRB has requested a notification frequency that is too high). + In such a case, the request would not fail, but the updated, + acceptable values would be reported in the <mrbresponse> accordingly. + +5.1.4. <mrbresponse> + + Responses to requests are indicated by an <mrbresponse> element. + + The <mrbresponse> element has the following attributes: + + status: numeric code indicating the response status. The attribute + MUST be present. + + reason: string specifying a reason for the response status. The + attribute MAY be present. + + The <mrbresponse> element has a single child element: + + <subscription> for providing details related to a subscription + requested by a Media Server (see below in this section). + + + + + + + + + + +Boulton, et al. Standards Track [Page 17] + +RFC 6917 Media Resource Brokering April 2013 + + + The following status codes are defined for 'status': + + +-----------+-------------------------------------------------------+ + | code | description | + +-----------+-------------------------------------------------------+ + | 200 | OK | + | | | + | 400 | Syntax error | + | | | + | 401 | Unable to create Subscription | + | | | + | 402 | Unable to update Subscription | + | | | + | 403 | Unable to remove Subscription | + | | | + | 404 | Subscription does not exist | + | | | + | 405 | Wrong sequence number | + | | | + | 406 | Subscription already exists | + | | | + | 420 | Unsupported attribute or element | + +-----------+-------------------------------------------------------+ + + Table 1: <mrbresponse> Status Codes + + If a new subscription request made by an MRB (action='create') has + been accepted, the Media Server MUST reply with an <mrbresponse> with + status code 200. The same rule applies whenever a request to update + (action='update') or remove (action='remove') an existing transaction + can be fulfilled by the Media Server. + + A subscription request, nevertheless, may fail for several reasons. + In such a case, the status codes defined in Table 1 must be used + instead. Specifically, if the Media Server fails to handle a request + due to a syntax error in the request itself (e.g., incorrect XML, + violation of the schema constraints, or invalid values in any of the + attributes/elements), the Media Server MUST reply with an + <mrbresponse> with status code 400. If a syntactically correct + request fails because the request also includes any attribute/element + the Media Server doesn't understand, the Media Server MUST reply with + an <mrbresponse> with status code 420. If a syntactically correct + request fails because the MRB wants to create a new subscription, but + the provided unique 'id' for the subscription already exists, the + Media Server MUST reply with an <mrbresponse> with status code 406. + If a syntactically correct request fails because the MRB wants to + update/remove a subscription that doesn't exist, the Media Server + MUST reply with an <mrbresponse> with status code 404. If the Media + + + +Boulton, et al. Standards Track [Page 18] + +RFC 6917 Media Resource Brokering April 2013 + + + Server is unable to accept a request for any other reason (e.g., the + MRB has no more resources to fulfill the request), the Media Server + MUST reply with an <mrbresponse> with status code 401/402/403, + depending on the action the MRB provided in its request: + + o action='create' --> 401; + + o action='update' --> 402; + + o action='remove' --> 403; + + A response to a subscription request that has a status code of 200 + indicates that the request is successful. The response MAY also + contain a <subscription> child that describes the subscription. The + <subscription> child MAY contain 'expires', 'minfrequency', and + 'maxfrequency' values even if they were not contained in the request. + + The Media Server can choose to change the suggested 'expires', + 'minfrequency', and 'maxfrequency' values provided by the MRB in its + <mrbrequest> if it considers them unacceptable (e.g., the requested + frequency range is too high). In such a case, the response MUST + contain a <subscription> element describing the subscription as the + Media Server accepted it, and the Media Server MUST include in the + <subscription> element all of those values that it modified relative + to the request, to inform the MRB about the change. + +5.1.5. <mrbnotification> + + The <mrbnotification> element is included in a request from a Media + Server to an MRB to provide the details relating to current status. + The Media Server will inform the MRB of its current status as defined + by the information in the <subscription> element. Updates are sent + using the <mrbnotification> element. + + The <mrbnotification> element has the following attributes: + + id: indicates a unique token representing the session between the + MRB and the Media Server and is the same as the one appearing in + the <subscription> element. The attribute MUST be present. + + seqnumber: indicates a sequence number to be used in conjunction + with the subscription session ID to identify a specific + notification update. The first notification update MUST contain a + non-zero number 'seqnumber', and subsequent notification updates + MUST contain a higher number than the previous 'seqnumber' value. + If a subsequent 'seqnumber' is not higher, the situation should be + + + + + +Boulton, et al. Standards Track [Page 19] + +RFC 6917 Media Resource Brokering April 2013 + + + considered an error by the entity receiving the notification + update. How the receiving entity deals with this situation is + implementation specific. The attribute MUST be present. + + It's important to point out that the 'seqnumber' that appears in an + <mrbnotification> is not related to the 'seqnumber' appearing in a + <subscription>. In fact, the latter is associated with subscriptions + and would increase at every command issued by the MRB, while the + former is associated with the asynchronous notifications the Media + Server would trigger according to the subscription and as such would + increase at every notification message to enable the MRB to keep + track of them. + + The following sub-sections provide details of the child elements that + make up the contents of the <mrbnotification> element. + +5.1.5.1. <media-server-id> + + The <media-server-id> element provides a unique system-wide + identifier for a Media Server instance. The element MUST be present + and MUST be chosen such that it is extremely unlikely that two + different Media Servers would present the same id to a given MRB. + +5.1.5.2. <supported-packages> + + The <supported-packages> element provides the list of Media Control + Channel packages supported by the Media Server. The element MAY be + present. + + The <supported-packages> element has no attributes. + + The <supported-packages> element has a single child element: + + <package>: Gives the name of a package supported by the Media + Server. The <package> element has a single attribute, 'name', + which provides the name of the supported Media Control Channel + Framework package, compliant with Section 13.1.1 of [RFC6230]. + +5.1.5.3. <active-rtp-sessions> + + The <active-rtp-sessions> element provides information detailing the + current active Real-time Transport Protocol (RTP) sessions. The + element MAY be present. + + The <active-rtp-sessions> element has no attributes. + + + + + + +Boulton, et al. Standards Track [Page 20] + +RFC 6917 Media Resource Brokering April 2013 + + + The <active-rtp-sessions> element has a single child element: + + <rtp-codec>: Describes a supported codec and the number of active + sessions using that codec. The <rtp-codec> element has one + attribute. The value of the attribute, 'name', is a media type + (which can include parameters per [RFC6381]). The <rtp-codec> + element has two child elements. The child element <decoding> has + as content the decimal number of RTP sessions being decoded using + the specified codec, and the child element <encoding> has as + content the decimal number of RTP sessions being encoded using the + specified codec. + +5.1.5.4. <active-mixer-sessions> + + The <active-mixer-sessions> element provides information detailing + the current active mixed RTP sessions. The element MAY be present. + + The <active-mixer-sessions> element has no attributes. + + The <active-mixer-sessions> element has a single child element: + + <active-mix>: Describes a mixed active RTP session. The + <active-mix> element has one attribute. The value of the + attribute, 'conferenceid', is the name of the mix. The + <active-mix> element has one child element. The child element, + <rtp-codec>, contains the same information relating to RTP + sessions as that defined in Section 5.1.5.3. The element MAY be + present. + +5.1.5.5. <non-active-rtp-sessions> + + The <non-active-rtp-sessions> element provides information detailing + the currently available inactive RTP sessions, that is, how many more + RTP streams this Media Server can support. The element MAY be + present. + + The <non-active-rtp-sessions> element has no attributes. + + The <non-active-rtp-sessions> element has a single child element: + + <rtp-codec>: Describes a supported codec and the number of + non-active sessions for that codec. The <rtp-codec> element has + one attribute. The value of the attribute, 'name', is a media + type (which can include parameters per [RFC6381]). The + <rtp-codec> element has two child elements. The child element + <decoding> has as content the decimal number of RTP sessions + + + + + +Boulton, et al. Standards Track [Page 21] + +RFC 6917 Media Resource Brokering April 2013 + + + available for decoding using the specified codec, and the child + element <encoding> has as content the decimal number of RTP + sessions available for encoding using the specified codec. + +5.1.5.6. <non-active-mixer-sessions> + + The <non-active-mixer-sessions> element provides information + detailing the current inactive mixed RTP sessions, that is, how many + more mixing sessions this Media Server can support. The element MAY + be present. + + The <non-active-mixer-sessions> element has no attributes. + + The <non-active-mixer-sessions> element has a single child element: + + <non-active-mix>: Describes available mixed RTP sessions. The + <non-active-mix> element has one attribute. The value of the + attribute, 'available', is the number of mixes that could be used + using that profile. The <non-active-mix> element has one child + element. The child element, <rtp-codec>, contains the same + information relating to RTP sessions as that defined in + Section 5.1.5.5. The element MAY be present. + +5.1.5.7. <media-server-status> + + The <media-server-status> element provides information detailing the + current status of the Media Server. The element MUST be present. It + can return one of the following values: + + active: Indicates that the Media Server is available for service. + + deactivated: Indicates that the Media Server has been withdrawn from + service, and as such requests should not be sent to it before it + becomes 'active' again. + + unavailable: Indicates that the Media Server continues to process + past requests but cannot accept new requests, and as such should + not be contacted before it becomes 'active' again. + + The <media-server-status> element has no attributes. + + The <media-server-status> element has no child elements. + + + + + + + + + +Boulton, et al. Standards Track [Page 22] + +RFC 6917 Media Resource Brokering April 2013 + + +5.1.5.8. <supported-codecs> + + The <supported-codecs> element provides information detailing the + current codecs supported by a Media Server and associated actions. + The element MAY be present. + + The <supported-codecs> element has no attributes. + + The <supported-codecs> element has a single child element: + + <supported-codec>: Has a single attribute, 'name', which provides + the name of the codec about which this element provides + information. A valid value is a media type that, depending on its + definition, can include additional parameters (e.g., [RFC6381]). + The <supported-codec> element then has a further child element, + <supported-codec-package>. The <supported-codec-package> element + has a single attribute, 'name', which provides the name of the + Media Control Channel Framework package, compliant with + Section 13.1.1 of [RFC6230], for which the codec support applies. + The <supported-codec-package> element has zero or more + <supported-action> children, each one of which describes an action + that a Media Server can apply to this codec: + + * 'decoding', meaning a decoder for this codec is available; + + * 'encoding', meaning an encoder for this codec is available; + + * 'passthrough', meaning the Media Server is able to pass a + stream encoded using that codec through, without re-encoding. + +5.1.5.9. <application-data> + + The <application-data> element provides an arbitrary string of + characters as application-level data. This data is meant to only + have meaning at the application-level logic and as such is not + otherwise restricted by this specification. The set of allowed + characters is the same as those in XML (viz., tab, carriage return, + line feed, and the legal characters of Unicode and ISO/IEC 10646 + [ISO.10646.2012] (see also Section 2.2 of + <http://www.w3.org/TR/xml/>)). The element MAY be present. + + The <application-data> element has no attributes. + + The <application-data> element has no child elements. + + + + + + + +Boulton, et al. Standards Track [Page 23] + +RFC 6917 Media Resource Brokering April 2013 + + +5.1.5.10. <file-formats> + + The <file-formats> element provides a list of file formats supported + for the purpose of playing media. The element MAY be present. + + The <file-formats> element has no attributes. + + The <file-formats> element has zero of more the following child + elements: + + <supported-format>: Has a single attribute, 'name', which provides + the type of file format that is supported. A valid value is a + media type that, depending on its definition, can include + additional parameters (e.g., [RFC6381]). The <supported-format> + element then has a further child element, + <supported-file-package>. The <supported-file-package> element + provides the name of the Media Control Channel Framework package, + compliant with Section 13.1.1 of [RFC6230], for which the file + format support applies. + +5.1.5.11. <max-prepared-duration> + + The <max-prepared-duration> element provides the maximum amount of + time a media dialog will be kept in the prepared state before timing + out (see Section 4.4.2.2.6 of RFC 6231 [RFC6231]. The element MAY be + present. + + The <max-prepared-duration> element has no attributes. + + The <max-prepared-duration> element has a single child element: + + <max-time>: Has a single attribute, 'max-time-seconds', which + provides the amount of time in seconds that a media dialog can be + in the prepared state. The <max-time> element then has a further + child element, <max-time-package>. The <max-time-package> element + provides the name of the Media Control Channel Framework package, + compliant with Section 13.1.1 of [RFC6230], for which the time + period applies. + + + + + + + + + + + + + +Boulton, et al. Standards Track [Page 24] + +RFC 6917 Media Resource Brokering April 2013 + + +5.1.5.12. <dtmf-support> + + The <dtmf-support> element specifies the supported methods to detect + Dual-Tone Multi-Frequency (DTMF) tones and to generate them. The + element MAY be present. + + The <dtmf-support> element has no attributes. + + The <dtmf-support> element has zero of more of the following child + elements: + + <detect>: Indicates the support for DTMF detection. The <detect> + element has no attributes. The <detect> element then has a + further child element, <dtmf-type>. The <dtmf-type> element has + two attributes: 'name' and 'package'. The 'name' attribute + provides the type of DTMF being used, and it can only be a case- + insensitive string containing either 'RFC4733' [RFC4733] or + 'Media' (detecting tones as signals from the audio stream). The + 'package' attribute provides the name of the Media Control Channel + Framework package, compliant with Section 13.1.1 of [RFC6230], for + which the DTMF type applies. + + <generate>: Indicates the support for DTMF generation. The + <generate> element has no attributes. The <generate> element then + has a further child element, <dtmf-type>. The <dtmf-type> element + has two attributes: 'name' and 'package'. The 'name' attribute + provides the type of DTMF being used, and it can only be a case- + insensitive string containing either 'RFC4733' [RFC4733] or + 'Media' (generating tones as signals in the audio stream). The + 'package' attribute provides the name of the Media Control Channel + Framework package, compliant with Section 13.1.1 of [RFC6230], for + which the DTMF type applies. + + <passthrough>: Indicates the support for passing DTMF through + without re-encoding. The <passthrough> element has no attributes. + The <passthrough> element then has a further child element, + <dtmf-type>. The <dtmf-type> element has two attributes: 'name' + and 'package'. The 'name' attribute provides the type of DTMF + being used, and it can only be a case-insensitive string + containing either 'RFC4733' [RFC4733] or 'Media' (passing tones as + signals through the audio stream). The 'package' attribute + provides the name of the Media Control Channel Framework package, + compliant with Section 13.1.1 of [RFC6230], for which the DTMF + type applies. + + + + + + + +Boulton, et al. Standards Track [Page 25] + +RFC 6917 Media Resource Brokering April 2013 + + +5.1.5.13. <mixing-modes> + + The <mixing-modes> element provides information about the support for + audio and video mixing of a Media Server, specifically a list of + supported algorithms to mix audio and a list of supported video + presentation layouts. The element MAY be present. + + The <mixing-modes> element has no attributes. + + The <mixing-modes> element has zero or more of the following child + elements: + + <audio-mixing-modes>: Describes the available algorithms for audio + mixing. The <audio-mixing-modes> element has no attributes. The + <audio-mixing-modes> element has one child element. The child + element, <audio-mixing-mode>, contains a specific available + algorithm. Valid values for the <audio-mixing-mode> element are + algorithm names, e.g., 'nbest' and 'controller' as defined in + [RFC6505]. The element has a single attribute, 'package'. The + attribute 'package' provides the name of the Media Control Channel + Framework package, compliant with Section 13.1.1 of [RFC6230], for + which the algorithm support applies. + + <video-mixing-modes>: Describes the available video presentation + layouts and the supported functionality related to video mixing. + The <video-mixing-modes> element has two attributes: 'vas' and + 'activespeakermix'. The 'vas' attribute is of type boolean with a + value of 'true' indicating that the Media Server supports + automatic Voice Activated Switching. The 'activespeakermix' is of + type boolean with a value of 'true' indicating that the Media + Server is able to prepare an additional video stream for the + loudest speaker participant without its contribution. The + <video-mixing-modes> element has one child element. The child + element, <video-mixing-mode>, contains the name of a specific + video presentation layout. The name may refer to one of the + predefined video layouts defined in the XCON conference + information data model [RFC6501], or to non-XCON layouts as well, + as long as they are properly prefixed according to the schema they + belong to. The <video-mixing-mode> element has a single + attribute, 'package'. The attribute 'package' provides the name + of the Media Control Channel Framework package, compliant with + Section 13.1.1 of [RFC6230], for which the algorithm support + applies. + + + + + + + + +Boulton, et al. Standards Track [Page 26] + +RFC 6917 Media Resource Brokering April 2013 + + +5.1.5.14. <supported-tones> + + The <supported-tones> element provides information about which tones + a Media Server is able to play and recognize. In particular, the + support is reported by referring to both support for country codes + (ISO 3166-1 [ISO.3166-1]) and supported functionality (ITU-T + Recommendation Q.1950 [ITU-T.Q.1950]). The element MAY be present. + + The <supported-tones> element has no attributes. + + The <supported-tones> element has zero or more of the following child + elements: + + <supported-country-codes>: Describes the supported country codes + with respect to tones. The <supported-country-codes> element has + no attributes. The <supported-country-codes> element has one + child element. The child element, <country-code>, reports support + for a specific country code, compliant with the ISO 3166-1 + [ISO.3166-1] specification. The <country-code> element has a + single attribute, 'package'. The attribute 'package' provides the + name of the Media Control Channel Framework package, compliant + with Section 13.1.1 of [RFC6230], in which the tones from the + specified country code are supported. + + <supported-h248-codes>: Describes the supported H.248 codes with + respect to tones. The <supported-h248-codes> element has no + attributes. The <supported-h248-codes> element has one child + element. The child element, <h248-code>, reports support for a + specific H.248 code, compliant with the ITU-T Recommendation + Q.1950 [ITU-T.Q.1950] specification. The codes can be either + specific (e.g., cg/dt to only report the Dial Tone from the Call + Progress Tones package) or generic (e.g., cg/* to report all the + tones from the Call Progress Tones package), using wildcards. The + <h248-code> element has a single attribute, 'package'. The + attribute 'package' provides the name of the Media Control Channel + Framework package, compliant with Section 13.1.1 of [RFC6230], in + which the specified codes are supported. + +5.1.5.15. <file-transfer-modes> + + The <file-transfer-modes> element allows the Media Server to specify + which scheme names are supported for transferring files to a Media + Server for each Media Control Channel Framework package type, for + example, whether the Media Server supports fetching resources via + HTTP, HTTPS, NFS, etc. The element MAY be present. + + The <file-transfer-modes> element has no attributes. + + + + +Boulton, et al. Standards Track [Page 27] + +RFC 6917 Media Resource Brokering April 2013 + + + The <file-transfer-modes> element has a single child element: + + <file-transfer-mode>: Has two attributes: 'name' and 'package'. The + 'name' attribute provides the scheme name of the protocol that can + be used for file transfer (e.g., HTTP, HTTPS, NFS, etc.); the + value of the attribute is case insensitive. The 'package' + attribute provides the name of the Media Control Channel Framework + package, compliant with the specification in the related IANA + registry (e.g., "msc-ivr/1.0"), for which the scheme name applies. + + It is important to point out that this element provides no + information about whether or not the Media Server supports any flavor + of live streaming: for instance, a value of "HTTP" for the IVR + (Interactive Voice Response) Package would only mean the 'http' + scheme makes sense to the Media Server within the context of that + package. Whether or not the Media Server can make use of HTTP to + only fetch resources, or also to attach an HTTP live stream to a + call, is to be considered implementation specific to the Media Server + and irrelevant to the Application Server and/or MRB. Besides, the + Media Server supporting a scheme does not imply that it also supports + the related secure versions: for instance, if the Media Server + supports both HTTP and HTTPS, both the schemes will appear in the + element. A lack of the "HTTPS" value would need to be interpreted as + a lack of support for the 'https' scheme. + +5.1.5.16. <asr-tts-support> + + The <asr-tts-support> element provides information about the support + for Automatic Speech Recognition (ASR) and Text-to-Speech (TTS) + functionality in a Media Server. The functionality is reported by + referring to the supported languages (using ISO 639-1 [ISO.639.2002] + codes) regarding both ASR and TTS. The element MAY be present. + + The <asr-tts-support> element has no attributes. + + The <asr-tts-support> element has zero or more of the following child + elements: + + <asr-support>: Describes the available languages for ASR. The + <asr-support> element has no attributes. The <asr-support> + element has one child element. The child element, <language>, + reports that the Media Server supports ASR for a specific + language. The <language> element has a single attribute, + 'xml:lang'. The attribute 'xml:lang' contains the ISO 639-1 + [ISO.639.2002] code of the supported language. + + + + + + +Boulton, et al. Standards Track [Page 28] + +RFC 6917 Media Resource Brokering April 2013 + + + <tts-support>: Describes the available languages for TTS. The + <tts-support> element has no attributes. The <tts-support> + element has one child element. The child element, <language>, + reports that the Media Server supports TTS for a specific + language. The <language> element has a single attribute, + 'xml:lang'. The attribute 'xml:lang' contains the ISO 639-1 + [ISO.639.2002] code of the supported language. + +5.1.5.17. <vxml-support> + + The <vxml-support> element specifies if the Media Server supports + VoiceXML (VXML) and, if it does, through which protocols the support + is exposed (e.g., via the control framework, RFC 4240 [RFC4240], or + RFC 5552 [RFC5552]). The element MAY be present. + + The <vxml-support> element has no attributes. + + The <vxml-support> element has a single child element: + + <vxml-mode>: Has two attributes: 'package' and 'support'. The + 'package' attribute provides the name of the Media Control Channel + Framework package, compliant with Section 13.1.1 of [RFC6230], for + which the VXML support applies. The 'support' attribute provides + the type of VXML support provided by the Media Server (e.g., + RFC 5552 [RFC5552], RFC 4240 [RFC4240], or the IVR Package + [RFC6231]), and valid values are case-insensitive RFC references + (e.g., "rfc6231" to specify that the Media Server supports + VoiceXML as provided by the IVR Package [RFC6231]). + + The presence of at least one <vxml-mode> child element would indicate + that the Media Server does support VXML as specified by the child + element itself. An empty <vxml> element would otherwise indicate + that the Media Server does not support VXML at all. + +5.1.5.18. <media-server-location> + + The <media-server-location> element provides information about the + civic location of a Media Server. Its description makes use of the + Civic Address Schema standardized in RFC 5139 [RFC5139]. The element + MAY be present. More precisely, this section is entirely optional, + and it's implementation specific to fill it with just the details + each implementer deems necessary for any optimization that may be + needed. + + The <media-server-location> element has no attributes. + + + + + + +Boulton, et al. Standards Track [Page 29] + +RFC 6917 Media Resource Brokering April 2013 + + + The <media-server-location> element has a single child element: + + <civicAddress>: Describes the civic address location of the Media + Server, whose representation refers to Section 4 of RFC 5139 + [RFC5139]. + +5.1.5.19. <label> + + The <label> element allows a Media Server to declare a piece of + information that will be understood by the MRB. For example, the + Media Server can declare if it's a blue or green one. It's a string + to allow arbitrary values to be returned to allow arbitrary + classification. The element MAY be present. + + The <label> element has no attributes. + + The <label> element has no child elements. + +5.1.5.20. <media-server-address> + + The <media-server-address> element allows a Media Server to provide a + direct SIP URI where it can be reached (e.g., the URI that the + Application Server would call in order to set up a Control Channel + and relay SIP media dialogs). The element MAY be present. + + The <media-server-address> element has no attributes. + + The <media-server-address> element has no child elements. + +5.1.5.21. <encryption> + + The <encryption> element allows a Media Server to declare support for + encrypting RTP media streams using RFC 3711 [RFC3711]. The element + MAY be present. If the element is present, then the Media Server + supports DTLS-SRTP (a Secure Real-time Transport Protocol (SRTP) + extension for Datagram Transport Layer Security (DTLS)) [RFC5763]. + + The <encryption> element has no attributes. + + The <encryption> element has no child elements. + +5.2. Media Service Resource Consumer Interface + + The Media Server Consumer interface provides the ability for clients + of an MRB, such as Application Servers, to request an appropriate + Media Server to satisfy specific criteria. This interface allows a + client to pass detailed meta-information to the MRB to help select an + appropriate Media Server. The MRB is then able to make an informed + + + +Boulton, et al. Standards Track [Page 30] + +RFC 6917 Media Resource Brokering April 2013 + + + decision and provide the client with an appropriate Media Server + resource. The MRB Consumer interface includes both 1) the In-line + Aware MRB Mode (IAMM), which uses the Session Initiation Protocol + (SIP) and 2) the Query mode, which uses the Hypertext Transfer + Protocol (HTTP) [RFC2616]. The MRB Consumer interface does not + include the In-line Unaware Mode (IUMM), which is further explained + in Section 5.3. The following sub-sections provide guidance on + using the Consumer interface, which is represented by the + 'application/mrb-consumer+xml' media type in Section 11, with HTTP + and SIP. + +5.2.1. Query Mode/HTTP Consumer Interface Usage + + An appropriate interface for such a 'query' style interface is in + fact an HTTP usage. Using HTTP and XML combined reduces complexity + and encourages the use of common tools that are widely available in + the industry today. The following information explains the primary + operations required to request and then receive information from an + MRB, by making use of HTTP [RFC2616] and HTTPS [RFC2818] as transport + for a query for a media resource, and the appropriate response. + + The media resource query, as defined by the <mediaResourceRequest> + element from Section 11, MUST be carried in the body of an HTTP/HTTPS + POST request. The media type contained in the HTTP/HTTPS request/ + response MUST be 'application/mrb-consumer+xml'. This value MUST be + reflected in the appropriate HTTP headers, such as 'Content-Type' and + 'Accept'. The body of the HTTP/HTTPS POST request MUST only contain + an <mrbconsumer> root element with only one child + <mediaResourceRequest> element as defined in Section 11. + + The media resource response to a query, as defined by the + <mediaResourceResponse> element from Section 11, MUST be carried in + the body of an HTTP/HTTPS 200 response to the original HTTP/HTTPS + POST request. The media type contained in the HTTP/HTTPS request/ + response MUST be 'application/mrb-consumer+xml'. This value MUST be + reflected in the appropriate HTTP headers, such as 'Content-Type' and + 'Accept'. The body of the HTTP/HTTPS 200 response MUST only contain + an <mrbconsumer> root element with only one child + <mediaResourceResponse> element as defined in Section 11. + + When an Application Server wants to release previously awarded media + resources granted through a prior request/response exchange with an + MRB, it will send a new request with an <action> element with value + 'remove', as described in Section 5.2.3 ("Consumer Interface Lease + Mechanism"). + + + + + + +Boulton, et al. Standards Track [Page 31] + +RFC 6917 Media Resource Brokering April 2013 + + +5.2.2. In-Line Aware Mode/SIP Consumer Interface Usage + + This document provides a complete toolkit for MRB deployment that + includes the ability to interact with an MRB using SIP for the + Consumer interface. The following information explains the primary + operations required to request and then receive information from an + MRB, by making use of SIP [RFC3261] as transport for a request for + media resources, and the appropriate response when using IAMM as the + mode of operation (as discussed in Section 5.2.2.1). + + The use of IAMM, besides having the MRB select appropriate media + resources on behalf of a client application, includes setting up + either a Control Framework Control Channel between an Application + Server and one of the Media Servers (Section 5.2.2.1) or a media + dialog session between an Application Server and one of the Media + Servers (Section 5.2.2.2). Note that in either case the SIP URIs of + the selected Media Servers are made known to the requesting + Application Server in the SIP 200 OK response by means of one or more + <media-server-address> child elements in the <response-session-info> + element (Section 5.2.6). + +5.2.2.1. IAMM and Setting Up a Control Framework Control Channel + + The media resource request information, as defined by the + <mediaResourceRequest> element from Section 11, is carried in a SIP + INVITE request. The INVITE request will be constructed as it would + have been to connect to a Media Server, as defined by the Media + Control Channel Framework [RFC6230]. It should be noted that this + specification does not exclude the use of an offerless INVITE as + defined in RFC 3261 [RFC3261]. Using offerless INVITE messages to an + MRB can potentially cause confusion when applying resource selection + algorithms, and an MRB, like any other SIP device, can choose to + reject with a 4xx response. For an offerless INVITE to be treated + appropriately, additional contextual information would need to be + provided with the request; this is out of scope for this document. + The following additional steps MUST be followed when using the + Consumer interface: + + o The Consumer client will include a payload in the SIP INVITE + request of type 'multipart/mixed' [RFC2046]. One of the parts to + be included in the 'multipart/mixed' payload MUST be the + 'application/sdp' format, which is constructed as specified in the + Media Control Channel Framework [RFC6230]. + + o Another part of the 'multipart/mixed' payload MUST be of type + 'application/mrb-consumer+xml', as specified in this document and + defined in Section 11. The body part MUST be an XML document + without prolog and whose root element is <mediaResourceRequest>. + + + +Boulton, et al. Standards Track [Page 32] + +RFC 6917 Media Resource Brokering April 2013 + + + o The INVITE request will then be dispatched to the MRB, as defined + by [RFC6230]. + + On receiving a SIP INVITE request containing the multipart/mixed + payload as specified previously, the MRB will complete a number of + steps to fulfill the request. It will: + + o Extract the multipart MIME payload from the SIP INVITE request. + It will then use the contextual information provided by the client + in the 'application/mrb-consumer+xml' part to determine which + Media Server (or Media Servers, if more than one is deemed to be + needed) should be selected to service the request. + + o Extract the 'application/sdp' part from the payload and use it as + the body of a new SIP INVITE request for connecting the client to + one of the selected Media Servers, as defined in the Media Channel + Control Framework [RFC6230]. The policy the MRB follows to pick a + specific Media Server out of the Media Servers it selects is + implementation specific and out of scope for this document. It is + important to configure the SIP elements between the MRB and the + Media Server in such a way that the INVITE will not fork. In the + case of a failure in reaching the chosen Media Server, the MRB + SHOULD proceed to the next one, if available. + + If none of the available Media Servers can be reached, the MRB MUST + reply with a SIP 503 error message that includes a Retry-After header + with a non-zero value. The Application Server MUST NOT attempt to + set up a new session before the time that the MRB asked it to wait + has passed. + + If at least one Media Server is reachable, the MRB acts as a Back-to- + Back User Agent (B2BUA) that extracts the 'application/ + mrb-consumer+xml' information from the SIP INVITE request and then + sends a corresponding SIP INVITE request to the Media Server it has + selected, to negotiate a Control Channel as defined in the Media + Channel Control Framework [RFC6230]. + + In the case of a failure in negotiating the Control Channel with the + Media Server, the MRB SHOULD proceed to the next one, if available, + as explained above. If none of the available Media Servers can be + reached, or the negotiations of the Control Channel with all of them + fail, the MRB MUST reply with a SIP 503 error message that includes a + Retry-After header with a non-zero value. The Application Server + MUST NOT attempt to set up a new session before the time that the MRB + asked it to wait has expired. + + + + + + +Boulton, et al. Standards Track [Page 33] + +RFC 6917 Media Resource Brokering April 2013 + + + Once the MRB receives the SIP response from the selected media + resource (i.e., Media Server), it will in turn respond to the + requesting client (i.e., Application Server). + + The media resource response generated by an MRB to a request, as + defined by the <mediaResourceResponse> element from Section 11, MUST + be carried in the payload of a SIP 200 OK response to the original + SIP INVITE request. The SIP 200 OK response will be constructed as + it would have been to connect from a Media Server, as defined by the + Media Control Channel Framework [RFC6230]. The following additional + steps MUST be followed when using the Consumer interface: + + o Include a payload in the SIP 200 response of type 'multipart/ + mixed' as per RFC 2046 [RFC2046]. One of the parts to be included + in the 'multipart/mixed' payload MUST be the 'application/sdp' + format, which is constructed as specified in the Media Control + Channel Framework [RFC6230] and based on the incoming response + from the selected media resource. + + o Another part of the 'multipart/mixed' payload MUST be of type + 'application/mrb-consumer+xml', as specified in this document and + defined in Section 11. Only the <mediaResourceResponse> and its + child elements can be included in the payload. + + o The SIP 200 response will then be dispatched from the MRB. + + o A SIP ACK to the 200 response will then be sent back to the MRB. + + Considering that the use of SIP as a transport for Consumer + transactions may result in failure, the IAMM relies on a successful + INVITE transaction to address the previously discussed sequence + (using the 'seq' XML element) increment mechanism. This means that + if the INVITE is unsuccessful for any reason, the Application Server + MUST use the same 'seq' value as previously used for the next + Consumer request that it may want to send to the MRB for the same + session. + + An MRB implementation may be programmed to conclude that the + requested resources are no longer needed when it receives a SIP BYE + from the Application Server or Media Server that concludes the SIP + dialog that initiated the request, or when the lease (Section 5.2.3) + interval expires. + + + + + + + + + +Boulton, et al. Standards Track [Page 34] + +RFC 6917 Media Resource Brokering April 2013 + + +5.2.2.2. IAMM and Setting Up a Media Dialog + + This scenario is identical to the description in the previous section + for setting up a Control Framework Control Channel, with the + exception that the application/sdp payload conveys content + appropriate for setting up the media dialog to the media resource, as + per RFC 3261 [RFC3261], instead of setting up a Control Channel. + +5.2.3. Consumer Interface Lease Mechanism + + The Consumer interface defined in Sections 5.2 and 11 allows a client + to request an appropriate media resource based on information + included in the request (either an HTTP POST or SIP INVITE message). + In the case of success, the response that is returned to the client + MUST contain a <response-session-info> element in either the SIP 200 + or HTTP 200 response. The success response contains the description + of certain resources that have been reserved to a specific Consumer + client in a (new or revised) "resource session", which is identified + in the <response-session-info>. The resource session is a "lease", + in that the reservation is scheduled to expire at a particular time + in the future, releasing the resources to be assigned for other uses. + The lease may be extended or terminated earlier by future Consumer + client requests that identify and reference a specific resource + session. + + Before delving into the details of such a lease mechanism, it is + worth clarifying its role within the context of the Consumer + interface. As explained in Section 5.1, the knowledge the MRB has of + the resources of all the Media Servers it is provisioned to manage is + not real-time. How an MRB actually manages such resources is + implementation specific -- for example, an implementation may choose + to have the MRB keeping track and state of the allocated resources, + or simply rely on the Media Servers themselves to provide the + information using the Publish interface. Further information may + also be inferred by the signaling, in the case where an MRB is in the + path of media dialogs. + + + + + + + + + + + + + + + +Boulton, et al. Standards Track [Page 35] + +RFC 6917 Media Resource Brokering April 2013 + + + The <mediaResourceResponse> element returned from the MRB contains a + <response-session-info> element if the request is successful. The + <response-session-info> element has zero or more of the following + child elements, which provide the appropriate resource session + information: + + o <session-id> is a unique identifier that enables a Consumer client + and MRB to correlate future media resource requests related to an + initial media resource request. The <session-id> MUST be included + in all future related requests (see the <session-id> paragraph + later in this section, where constructing a subsequent request is + discussed). + + o <seq> is a numeric value returned to the Consumer client. On + issuing any future requests related to the media resource session + (as determined by the <session-id> element), the Consumer client + MUST increment the value returned in the <seq> element and include + it in the request (see the <seq> paragraph later in this section, + where constructing a subsequent request is discussed). Its value + is a non-negative integer that MUST be limited within the + 0..2^31-1 range. + + o <expires> provides a value indicating the number of seconds that + the request for media resources is deemed alive. The Consumer + client should issue a refresh of the request, as discussed later + in this section, if the expiry is due to fire and the media + resources are still required. + + o <media-server-address> provides information representing an + assigned Media Server. More instances of this element may appear + should the MRB assign more Media Servers to a Consumer request. + + The <mediaResourceRequest> element is used in subsequent Consumer + interface requests if the client wishes to manipulate the session. + The Consumer client MUST include the <session-info> element, which + enables the receiving MRB to determine an existing media resource + allocation session. The <session-info> element has the following + child elements, which provide the appropriate resource session + information to the MRB: + + o <session-id> is a unique identifier that allows a Consumer client + to indicate the appropriate existing media resource session to be + manipulated by the MRB for this request. The value was provided + by the MRB in the initial request for media resources, as + discussed earlier in this section (<session-id> element included + as part of the <session-info> element in the initial + <mediaResourceResponse>). + + + + +Boulton, et al. Standards Track [Page 36] + +RFC 6917 Media Resource Brokering April 2013 + + + o <seq> is a numeric value returned to the Consumer client in the + initial request for media resources, as discussed earlier in this + section (<seq> element included as part of the <session-info> + element in the initial <mediaResourceResponse>). On issuing any + future requests related to the specific media resource session (as + determined by the <session-id> element), the Consumer client MUST + increment the value returned in the <seq> element from the initial + response (contained in the <mediaResourceResponse>) for every new + request. The value of the <seq> element in requests acts as a + counter and when used in conjunction with the unique <session-id> + allows for unique identification of a request. As anticipated + before, the <seq> value is limited to the 0..2^31-1 range: in the + unlikely case that the counter increases to reach the highest + allowed value, the <seq> value MUST be set to 0. The first + numeric value for the <seq> element is not meant to be '1' but + SHOULD be generated randomly by the MRB: this is to reduce the + chances of a malicious MRB disrupting the session created by this + MRB, as explained in Section 12. + + o <action> provides the operation to be carried out by the MRB on + receiving the request: + + * The value of 'update' is a request by the Consumer client to + update the existing session on the MRB with alternate media + resource requirements. If the requested resource information + is identical to the existing MRB session, the MRB will attempt + a session refresh. If the information has changed, the MRB + will attempt to update the existing session with the new + information. If the operation is successful, the 200 status + code in the response is returned in the status attribute of the + <mediaResourceResponseType> element. If the operation is not + successful, a 409 status code in the response is returned in + the status attribute of the <mediaResourceResponseType> + element. + + * The value of 'remove' is a request by the Consumer client to + remove the session on the MRB. This provides a mechanism for + Consumer clients to release unwanted resources before they + expire. If the operation is successful, a 200 status code in + the response is returned in the status attribute of the + <mediaResourceResponseType> element. If the operation is not + successful, a 410 status code in the response is returned in + the status attribute of the <mediaResourceResponseType> + element. + + Omitting the 'action' attribute means requesting a new set of + resources. + + + + +Boulton, et al. Standards Track [Page 37] + +RFC 6917 Media Resource Brokering April 2013 + + + When used with HTTP, the <session-info> element MUST be included in + an HTTP POST message (as defined in [RFC2616]). When used with SIP, + the <session-info> element MUST instead be included in either a SIP + INVITE or a SIP re-INVITE (as defined in [RFC3261]), or in a SIP + UPDATE (as defined in [RFC3311]) request: in fact, any SIP dialog, be + it a new or an existing one, can be exploited to carry leasing + information, and as such new SIP INVITE messages can update other + leases as well as request a new one. + + With IAMM, the Application Server or Media Server will eventually + send a SIP BYE to end the SIP session, whether it was for a Control + Channel or a media dialog. That BYE contains no Consumer interface + lease information. + +5.2.4. <mrbconsumer> + + This section defines the XML elements for the Consumer interface. + The formal XML schema definition for the Consumer interface can be + found in Section 11. + + The root element is <mrbconsumer>. All other XML elements (requests, + responses) are contained within it. The MRB Consumer interface + request element is detailed in Section 5.2.5.1. The MRB Consumer + interface response element is detailed in Section 5.2.6.1. + + The <mrbconsumer> element has the following attributes: + + version: a token specifying the mrb-consumer package version. The + value is fixed as '1.0' for this version of the package. The + attribute MUST be present. + + The <mrbconsumer> element may have zero or more children of one of + the following child element types: + + <mediaResourceRequest> for sending a Consumer request. See + Section 5.2.5.1. + + <mediaResourceResponse> for sending a Consumer response. See + Section 5.2.6.1. + + + + + + + + + + + + +Boulton, et al. Standards Track [Page 38] + +RFC 6917 Media Resource Brokering April 2013 + + +5.2.5. Media Service Resource Request + + This section provides the element definitions for use in Consumer + interface requests. The requests are carried in the + <mediaResourceRequest> element. + +5.2.5.1. <mediaResourceRequest> + + The <mediaResourceRequest> element provides information for clients + wishing to query an external MRB entity. The <mediaResourceRequest> + element has a single mandatory attribute, 'id': this attribute + contains a random identifier, generated by the client, that will be + included in the response in order to map it to a specific request. + The <mediaResourceRequest> element has <generalInfo>, <ivrInfo>, and + <mixerInfo> as child elements. These three elements are used to + describe the requirements of a client requesting a Media Server and + are covered in Sections 5.2.5.1.1, 5.2.5.1.2, and 5.2.5.1.3, + respectively. + +5.2.5.1.1. <generalInfo> + + The <generalInfo> element provides general Consumer request + information that is neither IVR specific nor mixer specific. This + includes session information that can be used for subsequent requests + as part of the leasing mechanism described in Section 5.2.3. The + following sub-sections describe the <session-info> and <packages> + elements, as used by the <generalInfo> element. + +5.2.5.1.1.1. <session-info> + + The <session-info> element is included in Consumer requests when an + update is being made to an existing media resource session. The + ability to change and remove an existing media resource session is + described in more detail in Section 5.2.3. The element MAY be + present. + + The <session-info> element has no attributes. + + The <session-info> element has zero or more of the following child + elements: + + <session-id>: A unique identifier that explicitly references an + existing media resource session on the MRB. The identifier is + included to update the existing session and is described in more + detail in Section 5.2.3. + + + + + + +Boulton, et al. Standards Track [Page 39] + +RFC 6917 Media Resource Brokering April 2013 + + + <seq>: Used in association with the <session-id> element in a + subsequent request to update an existing media resource session on + an MRB. The <seq> number is incremented from its original value + returned in response to the initial request for media resources. + Its value is a non-negative integer that MUST be limited within + the 0..2^31-1 range. In the unlikely case that the counter + increases to reach the highest allowed value, the <seq> value MUST + be set to 0. More information about its use is provided in + Section 5.2.3. + + <action>: Provides the operation that should be carried out on an + existing media resource session on an MRB: + + * The value of 'update' instructs the MRB to attempt to update + the existing media resource session with the information + contained in the <ivrInfo> and <mixerInfo> elements. + + * The value of 'remove' instructs the MRB to attempt to remove + the existing media resource session. More information on its + use is provided in Section 5.2.3. + +5.2.5.1.1.2. <packages> + + The <packages> element provides a list of Media Control Channel + Framework compliant packages that are required by the Consumer + client. The element MAY be present. + + The <packages> element has no attributes. + + The <packages> element has a single child element: + + <package>: Contains a string representing the Media Control Channel + Framework package required by the Consumer client. The <package> + element can appear multiple times. A valid value is a Control + Package name compliant with Section 13.1.1 of [RFC6230]. + +5.2.5.1.2. <ivrInfo> + + The <ivrInfo> element provides information for general Consumer + request information that is IVR specific. The following sub-sections + describe the elements of the <ivrInfo> element: <ivr-sessions>, + <file-formats>, <dtmf>, <tones>, <asr-tts>, <vxml>, <location>, + <encryption>, <application-data>, <max-prepared-duration>, and + <file-transfer-modes>. + + + + + + + +Boulton, et al. Standards Track [Page 40] + +RFC 6917 Media Resource Brokering April 2013 + + +5.2.5.1.2.1. <ivr-sessions> + + The <ivr-sessions> element indicates the number of IVR sessions that + a Consumer client requires from a media resource. The element MAY be + present. + + The <ivr-sessions> element has no attributes. + + The <ivr-sessions> element has a single child element: + + <rtp-codec>: Describes a required codec and the number of sessions + using that codec. The <rtp-codec> element has one attribute. The + value of the attribute, 'name', is a media type (which can include + parameters per [RFC6381]). The <rtp-codec> element has two child + elements. The child element <decoding> contains the number of RTP + sessions required for decoding using the specified codec, and the + child element <encoding> contains the number of RTP sessions + required for encoding using the specified codec. + +5.2.5.1.2.2. <file-formats> + + The <file-formats> element provides a list of file formats required + for the purpose of playing media. It should be noted that this + element describes media types and might better have been named + "media-formats", but due to existing implementations the name + "file-formats" is being used. The element MAY be present. + + The <file-formats> element has no attributes. + + The <file-formats> element has a single child element: + + <required-format>: Has a single attribute, 'name', which provides + the type of file format that is required. A valid value is a + media type that, depending on its definition, can include + additional parameters (e.g., [RFC6381]). The <required-format> + element then has a further child element, <required-file-package>. + The <required-file-package> element has a single attribute, + 'required-file-package-name', which contains the name of the Media + Control Channel Framework package, compliant with Section 13.1.1 + of [RFC6230], for which the file format support applies. + + + + + + + + + + + +Boulton, et al. Standards Track [Page 41] + +RFC 6917 Media Resource Brokering April 2013 + + +5.2.5.1.2.3. <dtmf> + + The <dtmf> element specifies the required methods to detect DTMF + tones and to generate them. The element MAY be present. + + The <dtmf> element has no attributes. + + The <dtmf> element has zero or more of the following child elements: + + <detect>: Indicates the required support for DTMF detection. The + <detect> element has no attributes. The <detect> element has a + further child element, <dtmf-type>. The <dtmf-type> element has + two attributes: 'name' and 'package'. The 'name' attribute + provides the type of DTMF required and is a case-insensitive + string containing either 'RFC4733' [RFC4733] or 'Media' (detecting + tones as signals from the audio stream). The 'package' attribute + provides the name of the Media Control Channel Framework package, + compliant with Section 13.1.1 of [RFC6230], for which the DTMF + type applies. + + <generate>: Indicates the required support for DTMF generation. The + <generate> element has no attributes. The <generate> element has + a single child element, <dtmf-type>. The <dtmf-type> element has + two attributes: 'name' and 'package'. The 'name' attribute + provides the type of DTMF required and is a case-insensitive + string containing either 'RFC4733' [RFC4733] or 'Media' + (generating tones as signals in the audio stream). The 'package' + attribute provides the name of the Media Control Channel Framework + package, compliant with Section 13.1.1 of [RFC6230], for which the + DTMF type applies. + + <passthrough>: Indicates the required support for passing DTMF + through without re-encoding. The <passthrough> element has no + attributes. The <passthrough> element then has a further child + element, <dtmf-type>. The <dtmf-type> element has two attributes: + 'name' and 'package'. The 'name' attribute provides the type of + DTMF required and is a case-insensitive string containing either + 'RFC4733' [RFC4733] or 'Media' (passing tones as signals through + the audio stream). The 'package' attribute provides the name of + the Media Control Channel Framework package, compliant with + Section 13.1.1 of [RFC6230], for which the DTMF type applies. + + + + + + + + + + +Boulton, et al. Standards Track [Page 42] + +RFC 6917 Media Resource Brokering April 2013 + + +5.2.5.1.2.4. <tones> + + The <tones> element provides requested tones that a Media Server must + support for IVR. In particular, the request refers to both support + for country codes (ISO 3166-1 [ISO.3166-1]) and requested + functionality (ITU-T Recommendation Q.1950 [ITU-T.Q.1950]). The + element MAY be present. + + The <tones> element has no attributes. + + The <tones> element has zero or more of the following child elements: + + <country-codes>: Describes the requested country codes in relation + to tones. The <country-codes> element has no attributes. The + <country-codes> element has one child element. The child element, + <country-code>, requests a specific country code, compliant with + the ISO 3166-1 [ISO.3166-1] specification. The <country-code> + element has a single attribute, 'package'. The attribute + 'package' provides the name of the Media Control Channel Framework + package, compliant with Section 13.1.1 of [RFC6230], in which the + tones from the specified country code are requested. + + <h248-codes>: Describes the requested H.248 codes in relation to + tones. The <h248-codes> element has no attributes. The + <h248-codes> element has one child element. The child element, + <h248-code>, requests a specific H.248 code, compliant with the + ITU-T Recommendation Q.1950 [ITU-T.Q.1950] specification. The + codes can be either specific (e.g., cg/dt to only report the Dial + Tone from the Call Progress Tones package) or generic (e.g., cg/* + to report all the tones from the Call Progress Tones package), + using wildcards. The <h248-code> element has a single attribute, + 'package'. The attribute 'package' provides the name of the Media + Control Channel Framework package, compliant with Section 13.1.1 + of [RFC6230], in which the specified codes are requested. + +5.2.5.1.2.5. <asr-tts> + + The <asr-tts> element requests information about the support for + Automatic Speech Recognition (ASR) and Text-to-Speech (TTS) + functionality in a Media Server. The functionality is requested by + referring to the supported languages (using ISO 639-1 [ISO.639.2002] + codes) in relation to both ASR and TTS. The <asr-tts> element has no + attributes. The <asr-tts> element has zero or more of the following + child elements: + + <asr-support>: Describes the available languages for ASR. The + <asr-support> element has no attributes. The <asr-support> + element has one child element. The child element, <language>, + + + +Boulton, et al. Standards Track [Page 43] + +RFC 6917 Media Resource Brokering April 2013 + + + requests that the Media Server supports ASR for a specific + language. The <language> element has a single attribute, + 'xml:lang'. The attribute 'xml:lang' contains the ISO 639-1 + [ISO.639.2002] code of the supported language. + + <tts-support>: Describes the available languages for TTS. The + <tts-support> element has no attributes. The <tts-support> + element has one child element. The child element, <language>, + requests that the Media Server supports TTS for a specific + language. The <language> element has a single attribute, + 'xml:lang'. The attribute 'xml:lang' contains the ISO 639-1 + [ISO.639.2002] code of the supported language. + +5.2.5.1.2.6. <vxml> + + The <vxml> element specifies if the Consumer client requires VoiceXML + and, if so, which protocols are supported (e.g., via the control + framework, RFC 4240 [RFC4240], or RFC 5552 [RFC5552]). The element + MAY be present. + + The <vxml> element has a single child element: + + <vxml-mode>: Has two attributes: 'package' and 'require'. The + 'package' attribute provides the name of the Media Control Channel + Framework package, compliant with Section 13.1.1 of [RFC6230], for + which the VXML support applies. The 'require' attribute specifies + the type of VXML support required by the Consumer client (e.g., + RFC 5552 [RFC5552], RFC 4240 [RFC4240], or IVR Package [RFC6231]), + and valid values are case-insensitive RFC references (e.g., + "rfc6231" to specify that the client requests support for VoiceXML + as provided by the IVR Package [RFC6231]). + + The presence of at least one <vxml> child element would indicate that + the Consumer client requires VXML support as specified by the child + element itself. An empty <vxml> element would otherwise indicate + that the Consumer client does not require VXML support. + +5.2.5.1.2.7. <location> + + The <location> element requests a civic location for an IVR Media + Server. The request makes use of the Civic Address Schema + standardized in RFC 5139 [RFC5139]. The element MAY be present. + More precisely, this section is entirely optional and is + implementation specific in its level of population. + + The <location> element has no attributes. + + + + + +Boulton, et al. Standards Track [Page 44] + +RFC 6917 Media Resource Brokering April 2013 + + + The <location> element has a single child element: + + <civicAddress>: Describes the civic address location of the + requested Media Server, whose representation refers to Section 4 + of RFC 5139 [RFC5139]. + +5.2.5.1.2.8. <encryption> + + The <encryption> element allows a Consumer client to request support + for encrypting RTP media streams using RFC 3711 [RFC3711]. The + element MAY be present. If the element is present, then the Media + Server supports DTLS-SRTP [RFC5763]. + + The <encryption> element has no attributes. + + The <encryption> element has no child elements. + +5.2.5.1.2.9. <application-data> + + The <application-data> element provides an arbitrary string of + characters as IVR application-level data. This data is meant to only + have meaning at the application-level logic and as such is not + otherwise restricted by this specification. The set of allowed + characters is the same as those in XML (viz., tab, carriage return, + line feed, and the legal characters of Unicode and ISO/IEC 10646 + [ISO.10646.2012] (see also Section 2.2 of + <http://www.w3.org/TR/xml/>)). The element MAY be present. + + The <application-data> element has no attributes. + + The <application-data> element has no child elements. + +5.2.5.1.2.10. <max-prepared-duration> + + The <max-prepared-duration> element indicates the amount of time + required by the Consumer client representing media dialog preparation + in the system before it is executed. The element MAY be present. + + The <max-prepared-duration> element has no attributes. + + The <max-prepared-duration> element has a single child element: + + <max-time>: Has a single attribute, 'max-time-seconds', which + provides the amount of time in seconds that a media dialog can be + in the prepared state. The <max-time> element then has a further + child element, <max-time-package>. The <max-time-package> element + + + + + +Boulton, et al. Standards Track [Page 45] + +RFC 6917 Media Resource Brokering April 2013 + + + provides the name of the Media Control Channel Framework package, + compliant with Section 13.1.1 of [RFC6230], for which the time + period applies. + +5.2.5.1.2.11. <file-transfer-modes> + + The <file-transfer-modes> element allows the Consumer client to + specify which scheme names are required for file transfer to a Media + Server for each Media Control Channel Framework package type. For + example, does the Media Server support fetching media resources via + HTTP, HTTPS, NFS, etc.? The element MAY be present. + + The <file-transfer-modes> element has no attributes. + + The <file-transfer-modes> element has a single child element: + + <file-transfer-mode>: Has two attributes: 'name' and 'package'. The + 'name' attribute provides the scheme name of the protocol required + for fetching resources: valid values are case-insensitive scheme + names (e.g., HTTP, HTTPS, NFS, etc.). The 'package' attribute + provides the name of the Media Control Channel Framework package, + compliant with Section 13.1.1 of [RFC6230], for which the scheme + name applies. + + The same considerations relating to file transfer and live streaming + are explained further in Section 5.1.5.15 and apply here as well. + +5.2.5.1.3. <mixerInfo> + + The <mixerInfo> element provides information for general Consumer + request information that is mixer specific. The following + sub-sections describe the elements of the <mixerInfo> element: + <mixers>, <file-formats>, <dtmf>, <tones>, <mixing-modes>, + <application-data>, <location>, and <encryption>. + +5.2.5.1.3.1. <mixers> + + The <mixers> element provides information detailing the required + mixed RTP sessions. The element MAY be present. + + The <mixers> element has no attributes. + + The <mixers> element has a single child element: + + <mix>: Describes the required mixed RTP sessions. The <mix> element + has one attribute. The value of the attribute, 'users', is the + number of participants required in the mix. The <mix> element has + + + + +Boulton, et al. Standards Track [Page 46] + +RFC 6917 Media Resource Brokering April 2013 + + + one child element. The child element, <rtp-codec>, contains the + same information relating to RTP sessions as that defined in + Section 5.1.5.3. The element MAY be present. + +5.2.5.1.3.2. <file-formats> + + The <file-formats> element provides a list of file formats required + by the Consumer client for the purpose of playing media to a mix. + The element MAY be present. + + The <file-formats> element has no attributes. + + The <file-formats> element has a single child element: + + <required-format>: Has a single attribute, 'name', which provides + the type of file format supported. A valid value is a media type + that, depending on its definition, can include additional + parameters (e.g., [RFC6381]). The <required-format> element has a + child element, <required-file-package>. The + <required-file-package> element contains a single attribute, + 'required-file-package-name', which contains the name of the Media + Control Channel Framework package, compliant with Section 13.1.1 + of [RFC6230], for which the file format support applies. + +5.2.5.1.3.3. <dtmf> + + The <dtmf> element specifies the required methods to detect DTMF + tones and to generate them in a mix. The element MAY be present. + + The <dtmf> element has no attributes. + + The <dtmf> element has zero or more of the following child elements: + + <detect>: Indicates the required support for DTMF detection. The + <detect> element has no attributes. The <detect> element then has + a further child element, <dtmf-type>. The <dtmf-type> element has + two attributes: 'name' and 'package'. The 'name' attribute + provides the type of DTMF being used and is a case-insensitive + string containing either 'RFC4733' [RFC4733] or 'Media' (detecting + tones as signals from the audio stream). The 'package' attribute + provides the name of the Media Control Channel Framework package, + compliant with Section 13.1.1 of [RFC6230], for which the DTMF + type applies. + + <generate>: Indicates the required support for DTMF generation. The + <generate> element has no attributes. The <generate> element has + a single child element, <dtmf-type>. The <dtmf-type> element has + two attributes: 'name' and 'package'. The 'name' attribute + + + +Boulton, et al. Standards Track [Page 47] + +RFC 6917 Media Resource Brokering April 2013 + + + provides the type of DTMF being used and is a case-insensitive + string containing either 'RFC4733' [RFC4733] or 'Media' + (generating tones as signals in the audio stream). The 'package' + attribute provides the name of the Media Control Channel Framework + package, compliant with Section 13.1.1 of [RFC6230], for which the + DTMF type applies. + + <passthrough>: Indicates the required support for passing DTMF + through without re-encoding. The <passthrough> element has no + attributes. The <passthrough> element has a single child element, + <dtmf-type>. The <dtmf-type> element has two attributes: 'name' + and 'package'. The 'name' attribute provides the type of DTMF + being used and is a case-insensitive string containing either + 'RFC4733' [RFC4733] or 'Media' (passing tones as signals through + the audio stream). The 'package' attribute provides the name of + the Media Control Channel Framework package, compliant with + Section 13.1.1 of [RFC6230], for which the DTMF type applies. + +5.2.5.1.3.4. <tones> + + The <tones> element provides requested tones that a Media Server must + support for a mix. In particular, the request refers to both support + for country codes (ISO 3166-1 [ISO.3166-1]) and requested + functionality (ITU-T Recommendation Q.1950 [ITU-T.Q.1950]). The + element MAY be present. + + The <tones> element has no attributes. + + The <tones> element has zero or more of the following child elements: + + <country-codes>: Describes the requested country codes in relation + to tones. The <country-codes> element has no attributes. The + <country-codes> element has a single child element. The child + element, <country-code>, requests a specific country code, + compliant with the ISO 3166-1 [ISO.3166-1] specification. The + <country-code> element has a single attribute, 'package'. The + attribute 'package' provides the name of the Media Control Channel + Framework package, compliant with the specification in the related + IANA registry (e.g., "msc-ivr/1.0"), in which the tones from the + specified country code are requested. + + <h248-codes>: Describes the requested H.248 codes with respect to + tones. The <h248-codes> element has no attributes. The + <h248-codes> element has a single child element. The child + element, <h248-code>, requests a specific H.248 code, compliant + with the ITU-T Recommendation Q.1950 [ITU-T.Q.1950] specification. + The codes can be either specific (e.g., cg/dt to only report the + Dial Tone from the Call Progress Tones package) or generic (e.g., + + + +Boulton, et al. Standards Track [Page 48] + +RFC 6917 Media Resource Brokering April 2013 + + + cg/* to report all the tones from the Call Progress Tones + package), using wildcards. The <h248-code> element has a single + attribute, 'package'. The attribute 'package' provides the name + of the Media Control Channel Framework package, compliant with + Section 13.1.1 of [RFC6230], in which the specified codes are + requested. + +5.2.5.1.3.5. <mixing-modes> + + The <mixing-modes> element requests information relating to support + for audio and video mixing, more specifically a list of supported + algorithms to mix audio and a list of supported video presentation + layouts. The element MAY be present. + + The <mixing-modes> element has no attributes. + + The <mixing-modes> element has zero or more of the following child + elements: + + <audio-mixing-modes>: Describes the requested algorithms for audio + mixing. The <audio-mixing-modes> element has no attributes. The + <audio-mixing-modes> element has one child element. The child + element, <audio-mixing-mode>, contains a requested mixing + algorithm. Valid values for the <audio-mixing-mode> element are + algorithm names, e.g., 'nbest' and 'controller' as defined in + [RFC6505]. The element has a single attribute, 'package'. The + attribute 'package' provides the name of the Media Control Channel + Framework package, compliant with Section 13.1.1 of [RFC6230], for + which the algorithm support is requested. + + <video-mixing-modes>: Describes the requested video presentation + layouts for video mixing. The <video-mixing-modes> element has + two attributes: 'vas' and 'activespeakermix'. The 'vas' attribute + is of type boolean with a value of 'true' indicating that the + Consumer client requires automatic Voice Activated Switching. The + 'activespeakermix' attribute is of type boolean with a value of + 'true' indicating that the Consumer client requires an additional + video stream for the loudest speaker participant without its + contribution. The <video-mixing-modes> element has one child + element. The child element, <video-mixing-mode>, contains the + name of a specific video presentation layout. The name may refer + to one of the predefined video layouts defined in the XCON + conference information data model, or to non-XCON layouts as well, + as long as they are appropriately prefixed. The + <video-mixing-mode> element has a single attribute, 'package'. + The attribute 'package' provides the name of the Media Control + Channel Framework package, compliant with Section 13.1.1 of + [RFC6230], for which the algorithm support is requested. + + + +Boulton, et al. Standards Track [Page 49] + +RFC 6917 Media Resource Brokering April 2013 + + +5.2.5.1.3.6. <application-data> + + The <application-data> element provides an arbitrary string of + characters as mixer application-level data. This data is meant to + only have meaning at the application-level logic and as such is not + otherwise restricted by this specification. The set of allowed + characters is the same as those in XML (viz., tab, carriage return, + line feed, and the legal characters of Unicode and ISO/IEC 10646 + [ISO.10646.2012] (see also Section 2.2 of + <http://www.w3.org/TR/xml/>)). The element MAY be present. + + The <application-data> element has no attributes. + + The <application-data> element has no child elements. + +5.2.5.1.3.7. <location> + + The <location> element requests a civic location for a mixer Media + Server. The request makes use of the Civic Address Schema + standardized in RFC 5139 [RFC5139]. The element MAY be present. + More precisely, this section is entirely optional, and it's + implementation specific to fill it with just the details each + implementer deems necessary for any optimization that may be needed. + + The <location> element has no attributes. + + The <location> element has a single child element: + + <civicAddress>: Describes the civic address location of the + requested Media Server, whose representation refers to Section 4 + of RFC 5139 [RFC5139]. + +5.2.5.1.3.8. <encryption> + + The <encryption> element allows a Consumer client to request support + for encrypting mixed RTP media streams using RFC 3711 [RFC3711]. The + element MAY be present. If the element is present, then the Media + Server supports DTLS-SRTP [RFC5763]. + + The <encryption> element has no attributes. + + The <encryption> element has no child elements. + + + + + + + + + +Boulton, et al. Standards Track [Page 50] + +RFC 6917 Media Resource Brokering April 2013 + + +5.2.6. Media Service Resource Response + + This section provides the element definitions for use in Consumer + interface responses. The responses are carried in the + <mediaResourceResponse> element. + +5.2.6.1. <mediaResourceResponse> + + The <mediaResourceResponse> element provides information for clients + receiving response information from an external MRB entity. + + The <mediaResourceResponse> element has two mandatory attributes: + 'id' and 'status'. The 'id' attribute must contain the same value + that the client provided in the 'id' attribute in the + <mediaResourceRequest> to which the response is mapped. The 'status' + attribute indicates the status code of the operation. The following + status codes are defined for 'status': + + +-----------+-------------------------------------------------------+ + | code | description | + +-----------+-------------------------------------------------------+ + | 200 | OK | + | | | + | 400 | Syntax error | + | | | + | 405 | Wrong sequence number | + | | | + | 408 | Unable to find Resource | + | | | + | 409 | Unable to update Resource | + | | | + | 410 | Unable to remove Resource | + | | | + | 420 | Unsupported attribute or element | + +-----------+-------------------------------------------------------+ + + Table 2: <mediaResourceResponse> Status Codes + + If a new media resource request made by a client application has been + accepted, the MRB MUST reply with a <mediaResourceResponse> with + status code 200. The same rule applies whenever a request to update + (action='update') or remove (action='remove') an existing transaction + can be fulfilled by the MRB. + + A media resource request, nevertheless, may fail for several reasons. + In such a case, the status codes defined in Table 2 must be used + instead. Specifically, if the MRB fails to handle a request due to a + syntax error in the request itself (e.g., incorrect XML, violation of + + + +Boulton, et al. Standards Track [Page 51] + +RFC 6917 Media Resource Brokering April 2013 + + + the schema constraints, or invalid values in any of the attributes/ + elements), the MRB MUST reply with a <mediaResourceResponse> with + status code 400. If a syntactically correct request fails because + the request also includes any attribute/element the MRB doesn't + understand, the MRB MUST reply with a <mediaResourceResponse> with + status code 420. If a syntactically correct request fails because it + contains a wrong sequence number, that is, a 'seq' value not + consistent with the increment the MRB expects according to + Section 5.2.3, the MRB MUST reply with a <mediaResourceResponse> with + status code 405. If a syntactically correct request fails because + the MRB couldn't find any Media Server able to fulfill the + requirements presented by the Application Server in its request, the + MRB MUST reply with a <mediaResourceResponse> with status code 408. + If a syntactically correct request fails because the MRB couldn't + update an existing request according to the new requirements + presented by the Application Server in its request, the MRB MUST + reply with a <mediaResourceResponse> with status code 409. If a + syntactically correct request fails because the MRB couldn't remove + an existing request and release the related resources as requested by + the Application Server, the MRB MUST reply with a + <mediaResourceResponse> with status code 410. + + Further details on status codes 409 and 410 are included in + Section 5.2.3, where the leasing mechanism, along with its related + scenarios, is described in more detail. + + The <mediaResourceResponse> element has <response-session-info> as a + child element. This element is used to describe the response of a + Consumer interface query and is covered in the following sub-section. + +5.2.6.1.1. <response-session-info> + + The <response-session-info> element is included in Consumer + responses. This applies to responses to both requests for new + resources and requests to update an existing media resource session. + The ability to change and remove an existing media resource session + is described in more detail in Section 5.2.3. If the request was + successful, the <mediaResourceResponse> MUST have one + <response-session-info> child, which describes the media resource + session addressed by the request. If the request was not successful, + the <mediaResourceResponse> MUST NOT have a <response-session-info> + child. + + The <response-session-info> element has no attributes. + + + + + + + +Boulton, et al. Standards Track [Page 52] + +RFC 6917 Media Resource Brokering April 2013 + + + The <response-session-info> element has zero or more of the following + child elements: + + <session-id>: A unique identifier that explicitly references an + existing media resource session on the MRB. The identifier is + included to update the existing session and is described in more + detail in Section 5.2.3. + + <seq>: Used in association with the <session-id> element in a + subsequent request to update an existing media resource session on + an MRB. The <seq> number is incremented from its original value + returned in response to the initial request for media resources. + More information on its use is provided in Section 5.2.3. + + <expires>: Includes the number of seconds that the media resources + are reserved as part of this interaction. If the lease is not + refreshed before expiry, the MRB will reclaim the resources and + they will no longer be guaranteed. It is RECOMMENDED that a + minimum value of 300 seconds be used for the value of the + 'expires' attribute. It is also RECOMMENDED that a Consumer + client refresh the lease at an interval that is not too close to + the expiry time. A value of 80% of the timeout period could be + used. For example, if the timeout period is 300 seconds, the + Consumer client would refresh the transaction at 240 seconds. + More information on its use is provided in Section 5.2.3. + + <media-server-address>: Provides information to reach the Media + Server handling the requested media resource. One or more + instances of these elements may appear. The + <media-server-address> element has a single attribute named 'uri', + which supplies a SIP URI that reaches the specified Media Server. + It also has three optional elements: <connection-id>, + <ivr-sessions>, and <mixers>. The <ivr-sessions> and <mixers> + elements are defined in Sections 5.2.5.1.2.1 and 5.2.5.1.3.1, + respectively, and have the same meaning but are applied to + individual Media Server instances as a subset of the overall + resources reported in the <connection-id> element. If multiple + Media Servers are assigned in an IAMM operation, exactly one + <media-server-address> element, more specifically the Media Server + that provided the media dialog or CFW response, will have a + <connection-id> element. Additional information relating to the + use of the <connection-id> element for media dialogs is included + in Section 6. + + + + + + + + +Boulton, et al. Standards Track [Page 53] + +RFC 6917 Media Resource Brokering April 2013 + + +5.3. In-Line Unaware MRB Interface + + An entity acting as an In-line MRB can act in one of two roles for a + request, as introduced in Section 4.2: the In-line Unaware MRB Mode + (IUMM) of operation and the In-line Aware MRB Mode (IAMM) of + operation. This section further describes IUMM. + + It should be noted that the introduction of an MRB entity into the + network, as specified in this document, requires interfaces to be + implemented by those requesting Media Server resources (for example, + an Application Server). This applies when using the Consumer + interface as discussed in Sections 5.2.1 (Query mode) and 5.2.2 + (IAMM). An MRB entity can also act in a client-unaware mode when + deployed into the network. This allows any SIP-compliant client + entity, as defined by RFC 3261 [RFC3261] and its extensions, to send + requests to an MRB that in turn will select an appropriate Media + Server based on knowledge of Media Server resources it currently has + available transparently to the client entity. Using an MRB in this + mode allows for easy migration of current applications and services + that are unaware of the MRB concept and would simply require a + configuration change resulting in the MRB being set as a SIP outbound + proxy for clients requiring media services. + + With IUMM, the MRB may conclude that an assigned media resource is no + longer needed when it receives a SIP BYE from the Application Server + or Media Server that ends the SIP dialog that initiated the request. + + As with IAMM, in IUMM the SIP INVITE from the Application Server + could convey the application/sdp payload to either set up a media + dialog or a Control Framework Control Channel. In either case, in + order to permit the Application Server to associate a media dialog + with a Control Channel to the same Media Server, using the procedures + of [RFC6230] Section 6, the MRB should be acting as a SIP proxy (and + not a B2BUA). This allows the SIP URI of the targeted Media Server + to be transparently passed back to the Application Server in the SIP + response, resulting in a direct SIP dialog between the Application + Server and the Media Server. + + While IUMM has the least impact on legacy Application Servers, it + also provides the least versatility. See Section 8. + +6. MRB Acting as a B2BUA + + An MRB entity can act as a SIP Back-to-Back User Agent (B2BUA) or a + SIP Proxy Server as defined in RFC 3261 [RFC3261]. When an MRB acts + as a B2BUA, issues can arise when using Media Control Channel + packages such as the IVR [RFC6231] and mixer [RFC6505] packages. + Specifically, the framework attribute 'connectionid' as provided in + + + +Boulton, et al. Standards Track [Page 54] + +RFC 6917 Media Resource Brokering April 2013 + + + Appendix A ("Common Package Components") of [RFC6230] uses a + concatenation of the SIP dialog identifiers to be used for + referencing SIP dialogs within the Media Control Channel. When a + request traverses an MRB acting as a B2BUA, the SIP dialog + identifiers change, and so the 'connectionid' cannot be used as + intended due to this change. For this reason, when an MRB wishes to + act as a SIP B2BUA when handling a request from an Application Server + to set up a media dialog to a Media Server, it MUST include the + optional <connection-id> element in a Consumer interface response + with a value that provides the equivalent for the 'connectionid' + ('Local Dialog Tag' + 'Remote Dialog Tag') for the far side of the + B2BUA. If present, this value MUST be used as the value for the + 'connectionid' in packages where the Common Package Components are + used. The <connection-id> element MUST NOT be included in an HTTP + Consumer interface response. + + It is important to point out that although more Media Server + instances may be returned in a Consumer response (i.e., the MRB has + assigned more than one Media Server to a Consumer request to fulfill + the Application Server requirements), in IAMM the MRB will only act + as a B2BUA with a single Media Server. In this case, exactly one + <media-server-address> element, describing the media dialog or CFW + response, will have a <connection-id> element that will not be + included in any additional <media-server-address> elements. + +7. Multimodal MRB Implementations + + An MRB implementation may operate multimodally with a collection of + Application Server clients all sharing the same pool of media + resources. That is, an MRB may be simultaneously operating in Query + mode, IAMM, and IUMM. It knows in which mode to act on any + particular request from a client, depending on the context of the + request: + + o If the received request is an HTTP POST message with application/ + mrb-consumer+xml content, then the MRB processes it in Query mode. + + o If the received request is a SIP INVITE with application/ + mrb-consumer+xml content and application/sdp content, then the MRB + processes it in IAMM. + + o If the received request is a SIP INVITE without application/ + mrb-consumer+xml content but with application/sdp content, then + the MRB processes it in IUMM. + + + + + + + +Boulton, et al. Standards Track [Page 55] + +RFC 6917 Media Resource Brokering April 2013 + + +8. Relative Merits of Query Mode, IAMM, and IUMM + + At a high level, the possible Application Server MRB interactions can + be distinguished by the following basic types: + + a. Query mode - the client is requesting the assignment by the MRB + of suitable Media Server resources; + + b. IAMM/media dialog - the client is requesting the assignment by + the MRB of suitable Media Server resources and the establishment + of a media dialog to one of the Media Servers; + + c. IAMM/Control Channel - the client is requesting the assignment by + the MRB of suitable Media Server resources and the establishment + of a CFW Control Channel to one of the Media Servers; + + d. IUMM/media dialog - the client is requesting the establishment of + a media dialog to a Media Server resource; + + e. IUMM/Control Channel - the client is requesting the establishment + of a CFW Control Channel to a Media Server resource. + + Each type of interaction has advantages and disadvantages, where such + considerations relate to the versatility of what the MRB can provide, + technical aspects such as efficiency in different application + scenarios, complexity, delay, use with legacy Application Servers, or + use with the Media Control Channel Framework. Depending on the + characteristics of a particular setting that an MRB is intended to + support, some of the above interaction types may be more appropriate + than others. This section provides a few observations on relative + merits but is not intended to be exhaustive. Some constraints of a + given interaction type may be subtle. + + o Operation with other types of media control: Any of the types of + interactions work with the mechanisms described in RFC 4240 + [RFC4240] and RFC 5552 [RFC5552] where initial control + instructions are conveyed in the SIP INVITE from the Application + Server for the media dialog to the Media Server and subsequent + instructions may be fetched using HTTP. Query mode (a), IAMM/ + media dialog (b), and IUMM/media dialog (d) work with the Media + Server Markup Language (MSML) as per RFC 5707 [RFC5707] or the + Media Server Control Markup Language (MSCML) as per RFC 5022 + [RFC5022]. + + o As stated previously, IUMM has no interface impacts on an + Application Server. When using IUMM, the Application Server does + not specify the characteristics of the type of media resource it + requires, as the <mediaResourceRequest> element is not passed to + + + +Boulton, et al. Standards Track [Page 56] + +RFC 6917 Media Resource Brokering April 2013 + + + the MRB. For IUMM/media dialog (d), the MRB can deduce an + appropriate media resource on a best-effort basis using + information gleaned from examining information in the SIP INVITE. + This includes the SDP information for the media dialog, or initial + control information in the SIP Request-URI as per RFC 4240 + [RFC4240]. With IUMM/Control Channel (e), there is even less + information for the MRB to use. + + o If using IUMM/Control Channel (e), the subsequent sending of the + media dialog to the Media Server should not be done using IUMM/ + media dialog. That is, the SIP signaling to send the media dialog + to the selected Media Server must be directly between the + Application Server and that Media Server, and not through the MRB. + Unless resources can be confidentially identified, the MRB could + send the media dialog to a different Media Server. Likewise, if + using IUMM/media dialog (d), the subsequent establishment of a + Control Channel should not be done with IUMM/Control Channel (e) + unless definitive information is available. + + o Query mode (a) and IAMM/Control Channel (c) lend themselves to + requesting a pool of media resources (e.g., a number of IVR or + conferencing ports) in advance of use and retaining use over a + period of time, independent of whether there are media dialogs to + those resources at any given moment, whereas the other types of + interactions do not. This also applies to making a subsequent + request to increase or decrease the amount of resources previously + awarded. + + o While Query mode (a) and IAMM/Control Channel (c) are the most + versatile interaction types, the former is completely decoupled + from the use or non-use of a Control Channel, whereas the latter + requires the use of a Control Channel. + + o When Media Control Channel Framework Control Channels are to be + used in conjunction with the use of an MRB, Query mode (a) would + typically result in fewer such channels being established over + time, as compared to IAMM/Control Channel (c). That is because + the latter would involve setting up an additional Control Channel + every time an Application Server has a new request for an MRB for + media resources. + + + + + + + + + + + +Boulton, et al. Standards Track [Page 57] + +RFC 6917 Media Resource Brokering April 2013 + + +9. Examples + + This section provides examples of both the Publish and Consumer + interfaces. Both the Query mode and In-line mode are addressed. + + Note that due to RFC formatting conventions, this section often + splits HTTP, SIP/SDP, and CFW across lines whose content would exceed + 72 characters. A backslash character marks where this line folding + has taken place. This backslash, and its trailing CRLF and + whitespace, would not appear in the actual protocol contents. Also + note that the indentation of the XML content is only provided for + readability: actual messages will follow strict XML syntax, which + allows for but does not require indentation. + +9.1. Publish Example + + The following example assumes that a Control Channel has been + established and synced as described in the Media Control Channel + Framework ([RFC6230]). + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + + +Boulton, et al. Standards Track [Page 58] + +RFC 6917 Media Resource Brokering April 2013 + + + Figure 9 shows the subscription/notification mechanism the Publish + interface is based on, as defined in Section 5.1. The MRB subscribes + for information at the Media Server (message A1.), and the Media + Server accepts the subscription (A2.). Notifications are triggered + by the Media Server (B1.) and acknowledged by the MRB (B2.). + + MRB MS + | | + | A1. CONTROL (MRB subscription) | + |--------------------------------------------->| + | A2. 200 OK | + |<---------------------------------------------| + | | + . . + . . + | | + | |--+ collect + | | | up-to-date + | |<-+ info + | B1. CONTROL (MRB notification) | + |<---------------------------------------------| + | B2. 200 OK | + |--------------------------------------------->| + | | + . . + . . + + Figure 9: Publish Example: Sequence Diagram + + The rest of this section includes a full dump of the messages + associated with the previous sequence diagram, specifically: + + 1. the subscription (A1.), in an <mrbrequest> (CFW CONTROL); + + 2. the Media Server accepting the subscription (A2.), in an + <mrbresponse> (CFW 200); + + 3. a notification (B1.), in an <mrbnotification> (CFW CONTROL); + + 4. the ack to the notification (B2.), in a framework-level 200 + message (CFW 200). + + + + + + + + + + +Boulton, et al. Standards Track [Page 59] + +RFC 6917 Media Resource Brokering April 2013 + + +A1. MRB -> MS (CONTROL, publish request) +---------------------------------------- +CFW lidc30BZObiC CONTROL +Control-Package: mrb-publish/1.0 +Content-Type: application/mrb-publish+xml +Content-Length: 337 + +<?xml version="1.0" encoding="UTF-8" standalone="yes"?> +<mrbpublish version="1.0" xmlns="urn:ietf:params:xml:ns:mrb-publish"> + <mrbrequest> + <subscription action="create" seqnumber="1" id="p0T65U"> + <expires>600</expires> + <minfrequency>20</minfrequency> + <maxfrequency>20</maxfrequency> + </subscription> + </mrbrequest> +</mrbpublish> + + +A2. MRB <- MS (200 to CONTROL, request accepted) +------------------------------------------------ +CFW lidc30BZObiC 200 +Timeout: 10 +Content-Type: application/mrb-publish+xml +Content-Length: 139 + +<mrbpublish version="1.0" xmlns="urn:ietf:params:xml:ns:mrb-publish"> + <mrbresponse status="200" reason="OK: Request accepted"/> +</mrbpublish> + + +B1. MRB <- MS (CONTROL, event notification from MS) +--------------------------------------------------- +CFW 03fff52e7b7a CONTROL +Control-Package: mrb-publish/1.0 +Content-Type: application/mrb-publish+xml +Content-Length: 4226 + +<?xml version="1.0" encoding="UTF-8" standalone="yes"?> + <mrbpublish version="1.0" + xmlns="urn:ietf:params:xml:ns:mrb-publish"> + <mrbnotification seqnumber="1" id="QQ6J3c"> + <media-server-id>a1b2c3d4</media-server-id> + <supported-packages> + <package name="msc-ivr/1.0"/> + <package name="msc-mixer/1.0"/> + + + + + +Boulton, et al. Standards Track [Page 60] + +RFC 6917 Media Resource Brokering April 2013 + + + <package name="mrb-publish/1.0"/> + <package name="msc-example-pkg/1.0"/> + </supported-packages> + <active-rtp-sessions> + <rtp-codec name="audio/basic"> + <decoding>10</decoding> + <encoding>20</encoding> + </rtp-codec> + </active-rtp-sessions> + <active-mixer-sessions> + <active-mix conferenceid="7cfgs43"> + <rtp-codec name="audio/basic"> + <decoding>3</decoding> + <encoding>3</encoding> + </rtp-codec> + </active-mix> + </active-mixer-sessions> + <non-active-rtp-sessions> + <rtp-codec name="audio/basic"> + <decoding>50</decoding> + <encoding>40</encoding> + </rtp-codec> + </non-active-rtp-sessions> + <non-active-mixer-sessions> + <non-active-mix available="15"> + <rtp-codec name="audio/basic"> + <decoding>15</decoding> + <encoding>15</encoding> + </rtp-codec> + </non-active-mix> + </non-active-mixer-sessions> + <media-server-status>active</media-server-status> + <supported-codecs> + <supported-codec name="audio/basic"> + <supported-codec-package name="msc-ivr/1.0"> + <supported-action>encoding</supported-action> + <supported-action>decoding</supported-action> + </supported-codec-package> + <supported-codec-package name="msc-mixer/1.0"> + <supported-action>encoding</supported-action> + <supported-action>decoding</supported-action> + </supported-codec-package> + </supported-codec> + </supported-codecs> + <application-data>TestbedPrototype</application-data> + + + + + + +Boulton, et al. Standards Track [Page 61] + +RFC 6917 Media Resource Brokering April 2013 + + + <file-formats> + <supported-format name="audio/x-wav"> + <supported-file-package> + msc-ivr/1.0 + </supported-file-package> + </supported-format> + </file-formats> + <max-prepared-duration> + <max-time max-time-seconds="3600"> + <max-time-package>msc-ivr/1.0</max-time-package> + </max-time> + </max-prepared-duration> + <dtmf-support> + <detect> + <dtmf-type package="msc-ivr/1.0" name="RFC4733"/> + <dtmf-type package="msc-mixer/1.0" name="RFC4733"/> + </detect> + <generate> + <dtmf-type package="msc-ivr/1.0" name="RFC4733"/> + <dtmf-type package="msc-mixer/1.0" name="RFC4733"/> + </generate> + <passthrough> + <dtmf-type package="msc-ivr/1.0" name="RFC4733"/> + <dtmf-type package="msc-mixer/1.0" name="RFC4733"/> + </passthrough> + </dtmf-support> + <mixing-modes> + <audio-mixing-modes> + <audio-mixing-mode package="msc-ivr/1.0"> + nbest + </audio-mixing-mode> + </audio-mixing-modes> + <video-mixing-modes activespeakermix="true" vas="true"> + <video-mixing-mode package="msc-mixer/1.0"> + single-view + </video-mixing-mode> + <video-mixing-mode package="msc-mixer/1.0"> + dual-view + </video-mixing-mode> + <video-mixing-mode package="msc-mixer/1.0"> + dual-view-crop + </video-mixing-mode> + <video-mixing-mode package="msc-mixer/1.0"> + dual-view-2x1 + </video-mixing-mode> + <video-mixing-mode package="msc-mixer/1.0"> + dual-view-2x1-crop + </video-mixing-mode> + + + +Boulton, et al. Standards Track [Page 62] + +RFC 6917 Media Resource Brokering April 2013 + + + <video-mixing-mode package="msc-mixer/1.0"> + quad-view + </video-mixing-mode> + <video-mixing-mode package="msc-mixer/1.0"> + multiple-5x1 + </video-mixing-mode> + <video-mixing-mode package="msc-mixer/1.0"> + multiple-3x3 + </video-mixing-mode> + <video-mixing-mode package="msc-mixer/1.0"> + multiple-4x4 + </video-mixing-mode> + </video-mixing-modes> + </mixing-modes> + <supported-tones> + <supported-country-codes> + <country-code package="msc-ivr/1.0">GB</country-code> + <country-code package="msc-ivr/1.0">IT</country-code> + <country-code package="msc-ivr/1.0">US</country-code> + </supported-country-codes> + <supported-h248-codes> + <h248-code package="msc-ivr/1.0">cg/*</h248-code> + <h248-code package="msc-ivr/1.0">biztn/ofque</h248-code> + <h248-code package="msc-ivr/1.0">biztn/erwt</h248-code> + <h248-code package="msc-mixer/1.0">conftn/*</h248-code> + </supported-h248-codes> + </supported-tones> + <file-transfer-modes> + <file-transfer-mode package="msc-ivr/1.0" name="HTTP"/> + </file-transfer-modes> + <asr-tts-support> + <asr-support> + <language xml:lang="en"/> + </asr-support> + <tts-support> + <language xml:lang="en"/> + </tts-support> + </asr-tts-support> + <vxml-support> + <vxml-mode package="msc-ivr/1.0" support="RFC6231"/> + </vxml-support> + <media-server-location> + <civicAddress xml:lang="it"> + <country>IT</country> + <A1>Campania</A1> + <A3>Napoli</A3> + <A6>Via Claudio</A6> + <HNO>21</HNO> + + + +Boulton, et al. Standards Track [Page 63] + +RFC 6917 Media Resource Brokering April 2013 + + + <LMK>University of Napoli Federico II</LMK> + <NAM>Dipartimento di Informatica e Sistemistica</NAM> + <PC>80210</PC> + </civicAddress> + </media-server-location> + <label>TestbedPrototype-01</label> + <media-server-address>sip:MS1@ms.example.net</media-server-address> + <encryption/> + </mrbnotification> + </mrbpublish> + + +B2. MRB -> MS (200 to CONTROL) +------------------------------ +CFW 03fff52e7b7a 200 + +9.2. Consumer Examples + + As specified in Section 5.2, the Consumer interface can be involved + in two different modes: Query and In-line aware. When in Query mode, + Consumer messages are transported in HTTP messages: an example of + such an approach is presented in Section 9.2.1. When in In-line + aware mode, messages are instead transported as part of SIP + negotiations: considering that SIP negotiations may be related to + either the creation of a Control Channel or to a User Agent Client + (UAC) media dialog, two separate examples of such an approach are + presented in Section 9.2.2. + +9.2.1. Query Example + + The following example assumes that the interested Application Server + already knows the HTTP URL where an MRB is listening for Consumer + messages. + + + + + + + + + + + + + + + + + + +Boulton, et al. Standards Track [Page 64] + +RFC 6917 Media Resource Brokering April 2013 + + + Figure 10 shows the HTTP-based transaction between the Application + Server (AS, as shown in the figure) and the MRB. The Application + Server sends a Consumer request as payload of an HTTP POST message + (1.), and the MRB provides an answer in an HTTP 200 OK message (2.). + Specifically, as will be shown in the examples, the Application + Server is interested in 100 IVR ports: the MRB finds two Media + Servers that can satisfy the request (one providing 60 ports and the + other providing 40 ports) and reports them to the Application Server. + + AS MRB + | | + | 1. HTTP POST (Consumer request) | + |--------------------------------------------->| + | | + | | + | |--+ Parse request + | | | and see if any + | |<-+ MS applies + | | + | 2. 200 OK (Consumer response) | + |<---------------------------------------------| + | | + |--+ Parse response and | + | | start session (SIP/COMEDIA/CFW) | + |<-+ with first MS reported by MRB | + | | + . . + . . + + Figure 10: Consumer Example (Query): Sequence Diagram + + The rest of this section includes a full dump of the messages + associated with the previous sequence diagram, specifically: + + 1. the Consumer request (1.), in a <mediaResourceRequest> (HTTP + POST, Content-Type 'application/mrb-consumer+xml'); + + 2. the Consumer response (2.), in a <mediaResourceResponse> (HTTP + 200 OK, Content-Type 'application/mrb-consumer+xml'). + + + + + + + + + + + + +Boulton, et al. Standards Track [Page 65] + +RFC 6917 Media Resource Brokering April 2013 + + +1. AS -> MRB (HTTP POST, Consumer request) +------------------------------------------ +POST /Mrb/Consumer HTTP/1.1 +Content-Length: 893 +Content-Type: application/mrb-consumer+xml +Host: mrb.example.net:8080 +Connection: Keep-Alive +User-Agent: Apache-HttpClient/4.0.1 (java 1.5) + +<?xml version="1.0" encoding="UTF-8" standalone="yes"?> +<mrbconsumer version="1.0" xmlns="urn:ietf:params:xml:ns:mrb-consumer"> + <mediaResourceRequest id="gh11x23v"> + <generalInfo> + <packages> + <package>msc-ivr/1.0</package> + <package>msc-mixer/1.0</package> + </packages> + </generalInfo> + <ivrInfo> + <ivr-sessions> + <rtp-codec name="audio/basic"> + <decoding>100</decoding> + <encoding>100</encoding> + </rtp-codec> + </ivr-sessions> + <file-formats> + <required-format name="audio/x-wav"/> + </file-formats> + <file-transfer-modes> + <file-transfer-mode package="msc-ivr/1.0" name="HTTP"/> + </file-transfer-modes> + </ivrInfo> + </mediaResourceRequest> +</mrbconsumer> + + + + + + + + + + + + + + + + + +Boulton, et al. Standards Track [Page 66] + +RFC 6917 Media Resource Brokering April 2013 + + +2. AS <- MRB (200 to POST, Consumer response) +--------------------------------------------- +HTTP/1.1 200 OK +X-Powered-By: Servlet/2.5 +Server: Sun GlassFish Communications Server 1.5 +Content-Type: application/mrb-consumer+xml;charset=ISO-8859-1 +Content-Length: 1133 +Date: Mon, 12 Apr 2011 14:59:26 GMT + +<?xml version="1.0" encoding="UTF-8" standalone="yes"?> +<mrbconsumer version="1.0" xmlns="urn:ietf:params:xml:ns:mrb-consumer" > + <mediaResourceResponse reason="Resource found" status="200" + id="gh11x23v"> + <response-session-info> + <session-id>5t3Y4IQ84gY1</session-id> + <seq>9</seq> + <expires>3600</expires> + <media-server-address + uri="sip:MediaServer@ms.example.com:5080"> + <ivr-sessions> + <rtp-codec name="audio/basic"> + <decoding>60</decoding> + <encoding>60</encoding> + </rtp-codec> + </ivr-sessions> + </media-server-address> + <media-server-address + uri="sip:OtherMediaServer@pool.example.net:5080"> + <ivr-sessions> + <rtp-codec name="audio/basic"> + <decoding>40</decoding> + <encoding>40</encoding> + </rtp-codec> + </ivr-sessions> + </media-server-address> + </response-session-info> + </mediaResourceResponse> +</mrbconsumer> + + As the example shows, the request and response are associated by + means of the 'id' attribute (id="gh11x23v"). The MRB has picked '9' + as the random sequence number that needs to be incremented by the + Application Server for the subsequent request associated with the + same session. + + + + + + + +Boulton, et al. Standards Track [Page 67] + +RFC 6917 Media Resource Brokering April 2013 + + + The rest of the scenario is omitted for brevity. After having + received the 'mediaResourceResponse', the Application Server has the + URIs of two Media Servers able to fulfill its media requirements and + can start a control dialog with one or both of them. + +9.2.2. IAMM Examples + + Two separate examples are presented for the IAMM case: in fact, IAMM + can take advantage of two different approaches with respect to the + SIP dialogs to be exploited to carry Consumer messages, i.e., i) a + SIP control dialog to create a Control Channel, and ii) a UAC media + dialog to attach to a Media Server. To make things clearer for the + reader, the same Consumer request as the one presented in the Query + mode will be sent, in order to clarify how the behavior of the + involved parties may differ. + +9.2.2.1. IAMM Example: CFW-Based Approach + + The following example assumes that the interested Application Server + already knows the SIP URI of an MRB. + + Figure 11 shows the first approach, i.e., SIP-based transactions + between the Application Server, the MRB, and one Media Server that + the MRB chooses from the two that are allocated to fulfill the + request. The diagram is more complex than before. This is basically + a scenario envisaging the MRB as a B2BUA. The Application Server + sends a SIP INVITE (1.) containing both a CFW-related SDP and a + Consumer request (multipart body). The MRB sends a provisional + response to the Application Server (2.) and starts working on the + request. First of all, it makes use of the Consumer request from the + Application Server to determine which Media Servers should be + exploited. Once the right Media Servers have been chosen (MS1 and + MS2 in the example), the MRB sends a new SIP INVITE (3.) to one of + the Media Servers (MS1 in the example) by just including the SDP part + of the original request. That Media Server negotiates this INVITE as + specified in [RFC6230] (4., 5., 6.), providing the MRB with its own + CFW-related SDP. The MRB replies to the original Application Server + INVITE preparing a SIP 200 OK with another multipart body (7.): this + multipart body includes the Consumer response used by the MRB to + determine the right Media Servers and the SDP returned by the Media + Server (MS1) in (5.). The Application Server finally acknowledges + the 200 OK (8.), and can start a CFW connection towards that Media + Server (MS1). Since the MRB provided the Application Server with two + Media Server instances to fulfill its requirements, the Application + Server can use the URI in the <media-server-address> element in the + <mediaResourceResponse> that describes the other Media Server to + establish a CFW channel with that Media Server (MS2) as well. + + + + +Boulton, et al. Standards Track [Page 68] + +RFC 6917 Media Resource Brokering April 2013 + + + Please note that to ease the reading of the protocol contents a + simple '=_Part' is used whenever a boundary for a 'multipart/mixed' + payload is provided, instead of the actual boundary that would be + inserted in the SIP messages. + + AS MRB MS1 MS2 + | | | | + | 1. INVITE | | | + | (multipart/mixed) | | | + |---------------------->| | | + | 2. 100 (Trying) | | | + |<----------------------| | | + | |--+ Extract SDP and | | + | | | MRB payloads; handle | | + | |<-+ Consumer request to | | + | | pick MSs (MS1 and MS2) | | + | | | | + | | 3. INVITE | | + | | (only copy SDP from 1.) | | + | |-------------------------->| | + | | 4. 100 (Trying) | | + | |<--------------------------| | + | | |--+ Negotiate | + | | | | CFW Control | + | | |<-+ Channel | + | | 5. 200 OK | | + | |<--------------------------| | + | | 6. ACK | | + | |-------------------------->| | + | Prepare new +--| | | + | payload with | | | | + | SDP from MS and +->| | | + | Consumer reply | | | + | | | | + | 7. 200 OK | | | + | (multipart/mixed) | | | + |<----------------------| | | + | 8. ACK | | | + |---------------------->| | | + | | | | + |--+ Read Cons. reply | | | + | | and use SDP to | | | + |<-+ create CFW Chn. | | | + | | | | + | | | + | Create TCP CFW channel towards MS1 (if needed) | | + |-------------------------------------------------->| | + | | | + + + +Boulton, et al. Standards Track [Page 69] + +RFC 6917 Media Resource Brokering April 2013 + + + |<<############## TCP CONNECTION #################>>| | + | | | + | CFW SYNC | | + |++++++++++++++++++++++++++++++++++++++++++++++++++>| | + | | | + . . . . + . . . . + | | | + | Negotiate SIP control dialog with MS2 | + |<------------------------------------------------------------------>| + | Create TCP CFW channel towards MS2 as well (if needed) | + |------------------------------------------------------------------->| + | | + |<<######################## TCP CONNECTION ########################>>| + | | + | CFW SYNC | + |+++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++>| + | | + | | | | + . . . . + . . . . + + Figure 11: Consumer Example (IAMM/Control Channel): Sequence Diagram + + The rest of this section includes an almost full trace of the + messages associated with the previous sequence diagram. Only the + relevant SIP messages are shown (both the INVITEs and the 200 OKs), + and only the relevant headers are preserved for brevity (Content-Type + and multipart-related information). Specifically: + + 1. the original INVITE (1.) containing both a CFW-related SDP + (Connection-Oriented Media (COMEDIA) information to negotiate a + new Control Channel) and a Consumer <mediaResourceRequest>; + + 2. the INVITE sent by the MRB (acting as a B2BUA) to the Media + Server (3.), containing only the CFW-related SDP from the + original INVITE; + + 3. the 200 OK sent by the Media Server back to the MRB (5.) to + complete the CFW-related negotiation (SDP only); + + 4. the 200 OK sent by the MRB back to the Application Server in + response to the original INVITE (7.), containing both the + CFW-related information sent by the Media Server and a Consumer + <mediaResourceRequest> documenting the MRB's decision to use that + Media Server. + + + + + +Boulton, et al. Standards Track [Page 70] + +RFC 6917 Media Resource Brokering April 2013 + + +1. AS -> MRB (INVITE multipart/mixed) +------------------------------------- + [..] + Content-Type: multipart/mixed;boundary="=_Part" + + =_Part + Content-Type: application/sdp + + v=0 + o=- 2890844526 2890842807 IN IP4 as.example.com + s=MediaCtrl + c=IN IP4 as.example.com + t=0 0 + m=application 48035 TCP cfw + a=connection:new + a=setup:active + a=cfw-id:vF0zD4xzUAW9 + a=ctrl-package:msc-mixer/1.0 + a=ctrl-package:msc-ivr/1.0 + + =_Part + Content-Type: application/mrb-consumer+xml + + <?xml version="1.0" encoding="UTF-8" standalone="yes"?> + <mrbconsumer version="1.0" + xmlns="urn:ietf:params:xml:ns:mrb-consumer"> + <mediaResourceRequest id="pz78hnq1"> + <generalInfo> + <packages> + <package>msc-ivr/1.0</package> + <package>msc-mixer/1.0</package> + </packages> + </generalInfo> + <ivrInfo> + <ivr-sessions> + <rtp-codec name="audio/basic"> + <decoding>100</decoding> + <encoding>100</encoding> + </rtp-codec> + </ivr-sessions> + <file-formats> + <required-format name="audio/x-wav"/> + </file-formats> + <file-transfer-modes> + <file-transfer-mode package="msc-ivr/1.0" name="HTTP"/> + </file-transfer-modes> + </ivrInfo> + </mediaResourceRequest> + + + +Boulton, et al. Standards Track [Page 71] + +RFC 6917 Media Resource Brokering April 2013 + + + </mrbconsumer> + + =_Part + + +3. MRB -> MS (INVITE sdp only) +------------------------------ + [..] + Content-Type: application/sdp + + v=0 + o=- 2890844526 2890842807 IN IP4 as.example.com + s=MediaCtrl + c=IN IP4 as.example.com + t=0 0 + m=application 48035 TCP cfw + a=connection:new + a=setup:active + a=cfw-id:vF0zD4xzUAW9 + a=ctrl-package:msc-mixer/1.0 + a=ctrl-package:msc-ivr/1.0 + + +5. MRB <- MS (200 OK sdp) +------------------------- + [..] + Content-Type: application/sdp + + v=0 + o=lminiero 2890844526 2890842808 IN IP4 ms.example.net + s=MediaCtrl + c=IN IP4 ms.example.net + t=0 0 + m=application 7575 TCP cfw + a=connection:new + a=setup:passive + a=cfw-id:vF0zD4xzUAW9 + a=ctrl-package:msc-mixer/1.0 + a=ctrl-package:msc-ivr/1.0 + a=ctrl-package:mrb-publish/1.0 + a=ctrl-package:msc-example-pkg/1.0 + + + + + + + + + + +Boulton, et al. Standards Track [Page 72] + +RFC 6917 Media Resource Brokering April 2013 + + +7. AS <- MRB (200 OK multipart/mixed) +------------------------------------- + [..] + Content-Type: multipart/mixed;boundary="=_Part" + + =_Part + Content-Type: application/sdp + + v=0 + o=lminiero 2890844526 2890842808 IN IP4 ms.example.net + s=MediaCtrl + c=IN IP4 ms.example.net + t=0 0 + m=application 7575 TCP cfw + a=connection:new + a=setup:passive + a=cfw-id:vF0zD4xzUAW9 + a=ctrl-package:msc-mixer/1.0 + a=ctrl-package:msc-ivr/1.0 + a=ctrl-package:mrb-publish/1.0 + a=ctrl-package:msc-example-pkg/1.0 + + =_Part + Content-Type: application/mrb-consumer+xml + + <?xml version="1.0" encoding="UTF-8" standalone="yes"?> + <mrbconsumer version="1.0" + xmlns="urn:ietf:params:xml:ns:mrb-consumer" > + <mediaResourceResponse reason="Resource found" status="200" + id="pz78hnq1"> + <response-session-info> + <session-id>z1skKYZQ3eFu</session-id> + <seq>9</seq> + <expires>3600</expires> + <media-server-address + uri="sip:MediaServer@ms.example.com:5080"> + <connection-id>32pbdxZ8:KQw677BF</connection-id> + <ivr-sessions> + <rtp-codec name="audio/basic"> + <decoding>60</decoding> + <encoding>60</encoding> + </rtp-codec> + </ivr-sessions> + </media-server-address> + <media-server-address + uri="sip:OtherMediaServer@pool.example.net:5080"> + <ivr-sessions> + <rtp-codec name="audio/basic"> + + + +Boulton, et al. Standards Track [Page 73] + +RFC 6917 Media Resource Brokering April 2013 + + + <decoding>40</decoding> + <encoding>40</encoding> + </rtp-codec> + </ivr-sessions> + </media-server-address> + </response-session-info> + </mediaResourceResponse> + </mrbconsumer> + + =_Part + + As the previous example illustrates, the only difference in the + response that the MRB provides to the Application Server is in the + 'connection-id' attribute that is added to the first allocated Media + Server instance: this allows the Application Server to understand + that the MRB has sent the CFW channel negotiation to that specific + Media Server and that the connection-id to be used is the one + provided. This will be described in more detail in the following + section for the media dialog-based approach. + + The continuation of the scenario (the Application Server connecting + to MS1 to start the Control Channel and the related SYNC message, the + Application Server connecting to MS2 as well later on, all the media + dialogs being attached to either Media Server) is omitted for + brevity. + +9.2.2.2. IAMM Example: Media Dialog-Based Approach + + The following example assumes that the interested Application Server + already knows the SIP URI of an MRB. + + Figure 12 shows the second approach, i.e., SIP-based transactions + between a SIP client, the Application Server, the MRB, and the Media + Server that the MRB chooses. The interaction is basically the same + as previous examples (e.g., contents of the multipart body), but + considering that a new party is involved in the communication, the + diagram is slightly more complex than before. As before, the MRB + acts as a B2BUA. A UAC sends a SIP INVITE to a SIP URI handled by + the Application Server, since it is interested to its services (1.). + The Application Server sends a provisional response (2.) and, since + it doesn't have the resources yet, sends to the MRB a new SIP INVITE + (3.) containing both the UAC media-related SDP and a Consumer request + (multipart body). The MRB sends a provisional response to the + Application Server (4.) and starts working on the request. First of + all, it makes use of the Consumer request from the Application Server + to determine which Media Servers should be chosen. Once the Media + Server has been chosen, the MRB sends a new SIP INVITE to one of the + Media Servers by including the SDP part of the original request (5.). + + + +Boulton, et al. Standards Track [Page 74] + +RFC 6917 Media Resource Brokering April 2013 + + + The Media Server negotiates this INVITE as specified in [RFC6230] + (6., 7., 8.) to allocate the needed media resources to handle the new + media dialog, eventually providing the MRB with its own media-related + SDP. The MRB replies to the original Application Server INVITE + preparing a SIP 200 OK with a multipart body (9.): this multipart + body includes the Consumer response from the MRB indicating the + chosen Media Servers and the SDP returned by the Media Server in + (7.). The Application Server finally acknowledges the 200 OK (10.) + and ends the scenario by eventually providing the UAC with the SDP it + needs to set up the RTP channels with the chosen Media Server: a + separate direct SIP control dialog may be initiated by the + Application Server to the same Media Server in order to set up a + Control Channel to manipulate the media dialog. + + As with the IAMM/Control Channel example in the prior section, this + example has the MRB selecting Media Server resources across two Media + Server instances. The convention could be that the MRB sent the SIP + INVITE to the first Media Server in the list provided to the + Application Server in the Consumer response information. For the + sake of brevity, considerations related to connecting to the other + Media Servers as well are omitted, since they have already been + addressed in the previous section. + + Please note that to ease the reading of the protocol contents, a + simple '=_Part' is used whenever a boundary for a 'multipart/mixed' + payload is provided, instead of the actual boundary that would be + inserted in the SIP messages. + + + + + + + + + + + + + + + + + + + + + + + + +Boulton, et al. Standards Track [Page 75] + +RFC 6917 Media Resource Brokering April 2013 + + + UAC AS MRB MS + | | | | + | 1. INVITE | | | + | (media SDP) | | | + |-------------->| | | + | 2. 100 Trying | | | + |<--------------| | | + | | 3. INVITE | | + | | (multipart/mixed) | | + | |---------------------->| | + | | 4. 100 (Trying) | | + | |<----------------------| | + | | |--+ Extract SDP and | + | | | | MRB payloads; handle | + | | |<-+ Consumer request to | + | | | pick Media Servers | + | | | | + | | | 5. INVITE | + | | | (only copy SDP from 3.) | + | | |-------------------------->| + | | | 6. 100 (Trying) | + | | |<--------------------------| + | | | +--| + | | | Handle media dialog | | + | | | (connection-id) +->| + | | | | + | | | 7. 200 OK | + | | |<--------------------------| + | | | 8. ACK | + | | |-------------------------->| + | | Prepare new +--| | + | | payload with | | | + | | SDP from MS and +->| | + | | Consumer reply | | + | | | | + | | 9. 200 OK | | + | | (multipart/mixed) | | + | |<----------------------| | + | | 10. ACK | | + | |---------------------->| | + | | | | + | |--+ Read Cons. reply | | + | | | and send SDP | | + | |<-+ back to UAC | | + | 11. 200 OK | | | + |<--------------| | | + | 12. ACK | | | + |-------------->| | | + + + +Boulton, et al. Standards Track [Page 76] + +RFC 6917 Media Resource Brokering April 2013 + + + | | | | + |<<*************************** RTP *******************************>>| + | | | | + | |--+ Negotiate | | + | | | CFW channel | | + | |<-+ towards MS | | + | | (if needed) | | + . . . . + . . . . + | | | | + | | | + | | Create TCP CFW channel towards MS (if needed) | + | |-------------------------------------------------->| + | | | + | |<<############## TCP CONNECTION #################>>| + | | | + | | CFW SYNC | + | |++++++++++++++++++++++++++++++++++++++++++++++++++>| + | | | + . . . . + . . . . + + Figure 12: Consumer Example (IAMM/Media Dialog): Sequence Diagram + + The rest of this section includes a trace of the messages associated + with the previous sequence diagram. Only the relevant SIP messages + are shown (both the INVITEs and the 200 OKs), and only the relevant + headers are preserved for brevity (Content-Type, From/To, and + multipart-related information). Specifically: + + 1. the original INVITE (1.) containing the media-related SDP sent by + a UAC; + + 2. the INVITE sent by the AS to the MRB (3.), containing both the + media-related SDP and a Consumer <mediaResourceRequest>; + + 3. the INVITE sent by the MRB (acting as a B2BUA) to the Media + Server (5.), containing only the media-related SDP from the + original INVITE; + + 4. the 200 OK sent by the Media Server back to the MRB (7.) to + complete the media-related negotiation (SDP only); + + + + + + + + + +Boulton, et al. Standards Track [Page 77] + +RFC 6917 Media Resource Brokering April 2013 + + + 5. the 200 OK sent by the MRB back to the Application Server in + response to the original INVITE (9.), containing both the + media-related information sent by the Media Server and a Consumer + <mediaResourceRequest> documenting the MRB's decision to use that + Media Server; + + 6. the 200 OK sent by the Application Server back to the UAC to have + it set up the RTP channel(s) with the Media Server (11.). + + +1. UAC -> AS (INVITE with media SDP) +------------------------------------ + [..] + From: <sip:lminiero@users.example.com>;tag=1153573888 + To: <sip:mediactrlDemo@as.example.com> + [..] + Content-Type: application/sdp + + v=0 + o=lminiero 123456 654321 IN IP4 203.0.113.2 + s=A conversation + c=IN IP4 203.0.113.2 + t=0 0 + m=audio 7078 RTP/AVP 0 3 8 101 + a=rtpmap:0 PCMU/8000/1 + a=rtpmap:3 GSM/8000/1 + a=rtpmap:8 PCMA/8000/1 + a=rtpmap:101 telephone-event/8000 + a=fmtp:101 0-11 + m=video 9078 RTP/AVP 98 + + +3. AS -> MRB (INVITE multipart/mixed) +------------------------------------- + [..] + From: <sip:ApplicationServer@as.example.com>;tag=fd4fush5 + To: <sip:Mrb@mrb.example.org> + [..] + Content-Type: multipart/mixed;boundary="=_Part" + + =_Part + Content-Type: application/sdp + + v=0 + o=lminiero 123456 654321 IN IP4 203.0.113.2 + s=A conversation + c=IN IP4 203.0.113.2 + t=0 0 + + + +Boulton, et al. Standards Track [Page 78] + +RFC 6917 Media Resource Brokering April 2013 + + + m=audio 7078 RTP/AVP 0 3 8 101 + a=rtpmap:0 PCMU/8000/1 + a=rtpmap:3 GSM/8000/1 + a=rtpmap:8 PCMA/8000/1 + a=rtpmap:101 telephone-event/8000 + a=fmtp:101 0-11 + m=video 9078 RTP/AVP 98 + + =_Part + Content-Type: application/mrb-consumer+xml + + <?xml version="1.0" encoding="UTF-8" standalone="yes"?> + <mrbconsumer version="1.0" + xmlns="urn:ietf:params:xml:ns:mrb-consumer"> + <mediaResourceRequest id="ns56g1x0"> + <generalInfo> + <packages> + <package>msc-ivr/1.0</package> + <package>msc-mixer/1.0</package> + </packages> + </generalInfo> + <ivrInfo> + <ivr-sessions> + <rtp-codec name="audio/basic"> + <decoding>100</decoding> + <encoding>100</encoding> + </rtp-codec> + </ivr-sessions> + <file-formats> + <required-format name="audio/x-wav"/> + </file-formats> + <file-transfer-modes> + <file-transfer-mode package="msc-ivr/1.0" name="HTTP"/> + </file-transfer-modes> + </ivrInfo> + </mediaResourceRequest> + </mrbconsumer> + + =_Part + + + + + + + + + + + + +Boulton, et al. Standards Track [Page 79] + +RFC 6917 Media Resource Brokering April 2013 + + +5. MRB -> MS (INVITE sdp only) +------------------------------ + [..] + From: <sip:Mrb@mrb.example.org:5060>;tag=32pbdxZ8 + To: <sip:MediaServer@ms.example.com:5080> + [..] + Content-Type: application/sdp + + v=0 + o=lminiero 123456 654321 IN IP4 203.0.113.2 + s=A conversation + c=IN IP4 203.0.113.2 + t=0 0 + m=audio 7078 RTP/AVP 0 3 8 101 + a=rtpmap:0 PCMU/8000/1 + a=rtpmap:3 GSM/8000/1 + a=rtpmap:8 PCMA/8000/1 + a=rtpmap:101 telephone-event/8000 + a=fmtp:101 0-11 + m=video 9078 RTP/AVP 98 + + +7. MRB <- MS (200 OK sdp) +------------------------- + [..] + From: <sip:Mrb@mrb.example.org:5060>;tag=32pbdxZ8 + To: <sip:MediaServer@ms.example.com:5080>;tag=KQw677BF + [..] + Content-Type: application/sdp + + v=0 + o=lminiero 123456 654322 IN IP4 203.0.113.1 + s=MediaCtrl + c=IN IP4 203.0.113.1 + t=0 0 + m=audio 63442 RTP/AVP 0 3 8 101 + a=rtpmap:0 PCMU/8000 + a=rtpmap:3 GSM/8000 + a=rtpmap:8 PCMA/8000 + a=rtpmap:101 telephone-event/8000 + a=fmtp:101 0-15 + a=ptime:20 + a=label:7eda834 + m=video 33468 RTP/AVP 98 + a=rtpmap:98 H263-1998/90000 + a=fmtp:98 CIF=2 + a=label:0132ca2 + + + + +Boulton, et al. Standards Track [Page 80] + +RFC 6917 Media Resource Brokering April 2013 + + +9. AS <- MRB (200 OK multipart/mixed) +------------------------------------- + [..] + From: <sip:ApplicationServer@as.example.com>;tag=fd4fush5 + To: <sip:Mrb@mrb.example.org>;tag=117652221 + [..] + Content-Type: multipart/mixed;boundary="=_Part" + + =_Part + Content-Type: application/sdp + + v=0 + o=lminiero 123456 654322 IN IP4 203.0.113.1 + s=MediaCtrl + c=IN IP4 203.0.113.1 + t=0 0 + m=audio 63442 RTP/AVP 0 3 8 101 + a=rtpmap:0 PCMU/8000 + a=rtpmap:3 GSM/8000 + a=rtpmap:8 PCMA/8000 + a=rtpmap:101 telephone-event/8000 + a=fmtp:101 0-15 + a=ptime:20 + a=label:7eda834 + m=video 33468 RTP/AVP 98 + a=rtpmap:98 H263-1998/90000 + a=fmtp:98 CIF=2 + a=label:0132ca2 + + =_Part + Content-Type: application/mrb-consumer+xml + + <?xml version="1.0" encoding="UTF-8" standalone="yes"?> + <mrbconsumer version="1.0" + xmlns="urn:ietf:params:xml:ns:mrb-consumer" > + <mediaResourceResponse reason="Resource found" status="200" + id="ns56g1x0"> + <response-session-info> + <session-id>z1skKYZQ3eFu</session-id> + <seq>9</seq> + <expires>3600</expires> + <media-server-address + uri="sip:MediaServer@ms.example.com:5080"> + <connection-id>32pbdxZ8:KQw677BF</connection-id> + <ivr-sessions> + <rtp-codec name="audio/basic"> + <decoding>60</decoding> + <encoding>60</encoding> + + + +Boulton, et al. Standards Track [Page 81] + +RFC 6917 Media Resource Brokering April 2013 + + + </rtp-codec> + </ivr-sessions> + </media-server-address> + <media-server-address + uri="sip:OtherMediaServer@pool.example.net:5080"> + <ivr-sessions> + <rtp-codec name="audio/basic"> + <decoding>40</decoding> + <encoding>40</encoding> + </rtp-codec> + </ivr-sessions> + </media-server-address> + </response-session-info> + </mediaResourceResponse> + </mrbconsumer> + + =_Part + + +11. UAC <- AS (200 OK sdp) +-------------------------- + [..] + From: <sip:lminiero@users.example.com>;tag=1153573888 + To: <sip:mediactrlDemo@as.example.com>;tag=bcd47c32 + [..] + Content-Type: application/sdp + + v=0 + o=lminiero 123456 654322 IN IP4 203.0.113.1 + s=MediaCtrl + c=IN IP4 203.0.113.1 + t=0 0 + m=audio 63442 RTP/AVP 0 3 8 101 + a=rtpmap:0 PCMU/8000 + a=rtpmap:3 GSM/8000 + a=rtpmap:8 PCMA/8000 + a=rtpmap:101 telephone-event/8000 + a=fmtp:101 0-15 + a=ptime:20 + a=label:7eda834 + m=video 33468 RTP/AVP 98 + a=rtpmap:98 H263-1998/90000 + a=fmtp:98 CIF=2 + a=label:0132ca2 + + As the examples illustrate, as in the IAMM/Control Channel example, + the MRB provides the Application Server with a <media-server-address> + element in the Consumer response: the 'uri' attribute identifies the + + + +Boulton, et al. Standards Track [Page 82] + +RFC 6917 Media Resource Brokering April 2013 + + + specific Media Server to which the MRB has sent the SDP media + negotiation, and the 'connection-id' enables the Application Server + to identify to the Media Server the dialog between the MRB and Media + Server. This attribute is needed, since according to the framework + specification [RFC6230] the connection-id is built out of the From/To + tags of the dialog between the MRB and Media Server; since the MRB + acts as a B2BUA in this scenario, without that attribute the + Application Server does not know the relevant tags, thus preventing + the CFW protocol from working as expected. + + The continuation of the scenario (the Application Server connecting + to the Media Server to start the Control Channel, the SYNC message, + etc.) is omitted for brevity. + +10. Media Service Resource Publisher Interface XML Schema + + This section gives the XML Schema Definition + [W3C.REC-xmlschema-1-20041028] [W3C.REC-xmlschema-2-20041028] of the + "application/mrb-publish+xml" format. + +<?xml version="1.0" encoding="UTF-8"?> +<xsd:schema targetNamespace="urn:ietf:params:xml:ns:mrb-publish" + elementFormDefault="qualified" blockDefault="#all" + xmlns="urn:ietf:params:xml:ns:mrb-publish" + xmlns:fw="urn:ietf:params:xml:ns:control:framework-attributes" + xmlns:ca="urn:ietf:params:xml:ns:pidf:geopriv10:civicAddr" + xmlns:xsd="http://www.w3.org/2001/XMLSchema"> + + <xsd:annotation> + <xsd:documentation> + IETF MediaCtrl MRB 1.0 + + This is the schema of the IETF MediaCtrl MRB package. + + The schema namespace is urn:ietf:params:xml:ns:mrb-publish + + </xsd:documentation> + </xsd:annotation> + + + <!-- + ############################################################# + + SCHEMA IMPORTS + + ############################################################# + --> + + + + +Boulton, et al. Standards Track [Page 83] + +RFC 6917 Media Resource Brokering April 2013 + + + <xsd:import namespace="http://www.w3.org/XML/1998/namespace" + schemaLocation="http://www.w3.org/2001/xml.xsd"> + <xsd:annotation> + <xsd:documentation> + This import brings in the XML attributes for + xml:base, xml:lang, etc. + </xsd:documentation> + </xsd:annotation> + </xsd:import> + + <xsd:import + namespace="urn:ietf:params:xml:ns:control:framework-attributes" + schemaLocation="framework.xsd"> + <xsd:annotation> + <xsd:documentation> + This import brings in the framework attributes for + conferenceid and connectionid. + </xsd:documentation> + </xsd:annotation> + </xsd:import> + + <xsd:import + namespace="urn:ietf:params:xml:ns:pidf:geopriv10:civicAddr" + schemaLocation="civicAddress.xsd"> + <xsd:annotation> + <xsd:documentation> + This import brings in the civicAddress specification + from RFC 5139. + </xsd:documentation> + </xsd:annotation> + </xsd:import> + +<!-- + ##################################################### + + Extensible core type + + ##################################################### + --> + + <xsd:complexType name="Tcore"> + <xsd:annotation> + <xsd:documentation> + This type is extended by other (non-mixed) component types to + allow attributes from other namespaces. + </xsd:documentation> + </xsd:annotation> + + + + +Boulton, et al. Standards Track [Page 84] + +RFC 6917 Media Resource Brokering April 2013 + + + <xsd:sequence/> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:complexType> + + +<!-- + ##################################################### + + TOP-LEVEL ELEMENT: mrbpublish + + ##################################################### + --> + +<xsd:complexType name="mrbpublishType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:choice> + <xsd:element ref="mrbrequest" /> + <xsd:element ref="mrbresponse" /> + <xsd:element ref="mrbnotification" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:choice> + </xsd:sequence> + <xsd:attribute name="version" type="version.datatype" + use="required" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + + <xsd:element name="mrbpublish" type="mrbpublishType" /> + +<!-- + ##################################################### + + mrbrequest TYPE + + ##################################################### + --> + +<!-- mrbrequest --> + + <xsd:complexType name="mrbrequestType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + + + +Boulton, et al. Standards Track [Page 85] + +RFC 6917 Media Resource Brokering April 2013 + + + <xsd:element ref="subscription" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + + <xsd:element name="mrbrequest" type="mrbrequestType" /> + +<!-- subscription --> + +<xsd:complexType name="subscriptionType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element name="expires" type="xsd:nonNegativeInteger" + minOccurs="0" maxOccurs="1" /> + <xsd:element name="minfrequency" type="xsd:nonNegativeInteger" + minOccurs="0" maxOccurs="1" /> + <xsd:element name="maxfrequency" type="xsd:nonNegativeInteger" + minOccurs="0" maxOccurs="1" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute name="id" type="id.datatype" use="required" /> + <xsd:attribute name="seqnumber" type="xsd:nonNegativeInteger" + use="required" /> + <xsd:attribute name="action" type="action.datatype" + use="required" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + + <xsd:element name="subscription" type="subscriptionType" /> + + + + + + + + + + + + + + +Boulton, et al. Standards Track [Page 86] + +RFC 6917 Media Resource Brokering April 2013 + + +<!-- + ##################################################### + + mrbresponse TYPE + + ##################################################### + --> + +<!-- mrbresponse --> + + <xsd:complexType name="mrbresponseType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="subscription" minOccurs="0" maxOccurs="1" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute name="status" type="status.datatype" + use="required" /> + <xsd:attribute name="reason" type="xsd:string" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + + + <xsd:element name="mrbresponse" type="mrbresponseType" /> + +<!-- + ##################################################### + + mrbnotification TYPE + + ##################################################### + --> + +<!-- mrbnotification --> + +<xsd:complexType name="mrbnotificationType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element name="media-server-id" + type="subscriptionid.datatype"/> + <xsd:element ref="supported-packages" minOccurs="0" /> + <xsd:element ref="active-rtp-sessions" minOccurs="0" /> + <xsd:element ref="active-mixer-sessions" minOccurs="0" /> + + + +Boulton, et al. Standards Track [Page 87] + +RFC 6917 Media Resource Brokering April 2013 + + + <xsd:element ref="non-active-rtp-sessions" minOccurs="0" /> + <xsd:element ref="non-active-mixer-sessions" minOccurs="0" /> + <xsd:element ref="media-server-status" minOccurs="0" /> + <xsd:element ref="supported-codecs" minOccurs="0" /> + <xsd:element ref="application-data" minOccurs="0" + maxOccurs="unbounded" /> + <xsd:element ref="file-formats" minOccurs="0" /> + <xsd:element ref="max-prepared-duration" minOccurs="0" /> + <xsd:element ref="dtmf-support" minOccurs="0" /> + <xsd:element ref="mixing-modes" minOccurs="0" /> + <xsd:element ref="supported-tones" minOccurs="0" /> + <xsd:element ref="file-transfer-modes" minOccurs="0" /> + <xsd:element ref="asr-tts-support" minOccurs="0" /> + <xsd:element ref="vxml-support" minOccurs="0" /> + <xsd:element ref="media-server-location" minOccurs="0" /> + <xsd:element ref="label" minOccurs="0" /> + <xsd:element ref="media-server-address" minOccurs="0" /> + <xsd:element ref="encryption" minOccurs="0" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute name="id" type="subscriptionid.datatype" + use="required" /> + <xsd:attribute name="seqnumber" type="xsd:nonNegativeInteger" + use="required" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + + <xsd:element name="mrbnotification" type="mrbnotificationType" /> + + +<!-- supported-packages --> + + <xsd:complexType name="supported-packagesType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="package" minOccurs="0" + maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + + + +Boulton, et al. Standards Track [Page 88] + +RFC 6917 Media Resource Brokering April 2013 + + +<xsd:element name="supported-packages" type="supported-packagesType"/> + + + <xsd:complexType name="packageType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute name="name" type="xsd:string" use="required" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + + <xsd:element name="package" type="packageType" /> + + +<!-- active-rtp-sessions --> + + <xsd:complexType name="active-rtp-sessionsType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="rtp-codec" minOccurs="0" + maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + +<xsd:element name="active-rtp-sessions" type="active-rtp-sessionsType"/> + + + <xsd:complexType name="rtp-codecType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element name="decoding" type="xsd:nonNegativeInteger" /> + <xsd:element name="encoding" type="xsd:nonNegativeInteger" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute name="name" type="xsd:string" use="required" /> + + + +Boulton, et al. Standards Track [Page 89] + +RFC 6917 Media Resource Brokering April 2013 + + + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + + <xsd:element name="rtp-codec" type="rtp-codecType" /> + + +<!-- active-mixer-sessions --> + +<xsd:complexType name="active-mixer-sessionsType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="active-mix" minOccurs="0" + maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + + <xsd:element name="active-mixer-sessions" + type="active-mixer-sessionsType" /> + + +<xsd:complexType name="active-mixType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="rtp-codec" minOccurs="0" + maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attributeGroup ref="fw:framework-attributes" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + + <xsd:element name="active-mix" type="active-mixType" /> + + + + + + + +Boulton, et al. Standards Track [Page 90] + +RFC 6917 Media Resource Brokering April 2013 + + +<!-- non-active-rtp-sessions --> + +<xsd:complexType name="non-active-rtp-sessionsType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="rtp-codec" minOccurs="0" + maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + + <xsd:element name="non-active-rtp-sessions" + type="non-active-rtp-sessionsType" /> + +<!-- non-active-mixer-sessions --> + +<xsd:complexType name="non-active-mixer-sessionsType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="non-active-mix" minOccurs="0" + maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + + <xsd:element name="non-active-mixer-sessions" + type="non-active-mixer-sessionsType" /> + + <xsd:complexType name="non-active-mixType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="rtp-codec" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute name="available" type="xsd:nonNegativeInteger" + use="required" /> + + + +Boulton, et al. Standards Track [Page 91] + +RFC 6917 Media Resource Brokering April 2013 + + + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + + <xsd:element name="non-active-mix" type="non-active-mixType" /> + +<!-- media-server-status --> + + <xsd:element name="media-server-status" type="msstatus.datatype" /> + +<!-- supported-codecs --> + +<xsd:complexType name="supported-codecsType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="supported-codec" + minOccurs="0" maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + + <xsd:element name="supported-codecs" type="supported-codecsType" /> + + <xsd:complexType name="supported-codecType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="supported-codec-package" + minOccurs="0" maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute name="name" type="xsd:string" use="required" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + + <xsd:element name="supported-codec" type="supported-codecType" /> + + + + + + +Boulton, et al. Standards Track [Page 92] + +RFC 6917 Media Resource Brokering April 2013 + + + <xsd:complexType name="supported-codec-packageType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element name="supported-action" type="actions.datatype" + minOccurs="0" maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute name="name" type="xsd:string" use="required" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + + <xsd:element name="supported-codec-package" + type="supported-codec-packageType" /> + + +<!-- application-data --> + +<xsd:element name="application-data" type="appdata.datatype" /> + +<!-- file-formats --> + +<xsd:complexType name="file-formatsType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="supported-format" + minOccurs="0" maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + + <xsd:element name="file-formats" type="file-formatsType" /> + + <xsd:complexType name="supported-formatType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="supported-file-package" + minOccurs="0" maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + + + +Boulton, et al. Standards Track [Page 93] + +RFC 6917 Media Resource Brokering April 2013 + + + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute name="name" type="xsd:string" use="required" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + + <xsd:element name="supported-format" type="supported-formatType" /> + + <xsd:element name="supported-file-package" + type="xsd:string" /> + +<!-- max-prepared-duration --> + +<xsd:complexType name="max-prepared-durationType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="max-time" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + + <xsd:element name="max-prepared-duration" + type="max-prepared-durationType" /> + + + <xsd:complexType name="max-timeType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element name="max-time-package" type="xsd:string" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute name="max-time-seconds" type="xsd:nonNegativeInteger" + use="required" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + + <xsd:element name="max-time" type="max-timeType" /> + + + +Boulton, et al. Standards Track [Page 94] + +RFC 6917 Media Resource Brokering April 2013 + + +<!-- dtmf-support --> + +<xsd:complexType name="dtmf-supportType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="detect" /> + <xsd:element ref="generate" /> + <xsd:element ref="passthrough" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + + <xsd:element name="dtmf-support" type="dtmf-supportType" /> + + <xsd:complexType name="detectType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="dtmf-type" + minOccurs="0" maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + + <xsd:element name="detect" type="detectType" /> + + <xsd:complexType name="generateType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="dtmf-type" + minOccurs="0" maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + + + +Boulton, et al. Standards Track [Page 95] + +RFC 6917 Media Resource Brokering April 2013 + + + <xsd:element name="generate" type="generateType" /> + + <xsd:complexType name="passthroughType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="dtmf-type" + minOccurs="0" maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + + <xsd:element name="passthrough" type="passthroughType" /> + + + <xsd:complexType name="dtmf-typeType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute name="name" type="dtmf.datatype" use="required" /> + <xsd:attribute name="package" type="xsd:string" use="required" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + + <xsd:element name="dtmf-type" type="dtmf-typeType" /> + + +<!-- mixing-modes --> + +<xsd:complexType name="mixing-modesType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="audio-mixing-modes" + minOccurs="0" maxOccurs="1" /> + <xsd:element ref="video-mixing-modes" + minOccurs="0" maxOccurs="1" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + + + +Boulton, et al. Standards Track [Page 96] + +RFC 6917 Media Resource Brokering April 2013 + + + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="mixing-modes" type="mixing-modesType" /> + +<xsd:complexType name="audio-mixing-modesType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="audio-mixing-mode" + minOccurs="0" maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="audio-mixing-modes" type="audio-mixing-modesType" /> + +<xsd:complexType name="audio-mixing-modeType" mixed="true"> + <xsd:sequence> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute name="package" type="xsd:string" use="required" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> +</xsd:complexType> + +<xsd:element name="audio-mixing-mode" type="audio-mixing-modeType" /> + +<xsd:complexType name="video-mixing-modesType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="video-mixing-mode" + minOccurs="0" maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute name="vas" type="boolean.datatype" + default="false" /> + <xsd:attribute name="activespeakermix" type="boolean.datatype" + default="false" /> + + + +Boulton, et al. Standards Track [Page 97] + +RFC 6917 Media Resource Brokering April 2013 + + + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="video-mixing-modes" type="video-mixing-modesType" /> + +<xsd:complexType name="video-mixing-modeType" mixed="true"> + <xsd:sequence> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute name="package" type="xsd:string" use="required" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> +</xsd:complexType> + +<xsd:element name="video-mixing-mode" type="video-mixing-modeType" /> + + +<!-- supported-tones --> + +<xsd:complexType name="supported-tonesType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="supported-country-codes" + minOccurs="0" maxOccurs="1" /> + <xsd:element ref="supported-h248-codes" + minOccurs="0" maxOccurs="1" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="supported-tones" type="supported-tonesType" /> + +<xsd:complexType name="supported-country-codesType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="country-code" + minOccurs="0" maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + + + +Boulton, et al. Standards Track [Page 98] + +RFC 6917 Media Resource Brokering April 2013 + + + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="supported-country-codes" + type="supported-country-codesType" /> + +<xsd:complexType name="country-codeType" mixed="true"> + <xsd:sequence> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute name="package" type="xsd:string" use="required" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> +</xsd:complexType> + +<xsd:element name="country-code" type="country-codeType" /> + +<xsd:complexType name="supported-h248-codesType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="h248-code" + minOccurs="0" maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="supported-h248-codes" + type="supported-h248-codesType" /> + +<xsd:complexType name="h248-codeType" mixed="true"> + <xsd:sequence> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute name="package" type="xsd:string" use="required" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> +</xsd:complexType> + +<xsd:element name="h248-code" type="h248-codeType" /> + + + + + +Boulton, et al. Standards Track [Page 99] + +RFC 6917 Media Resource Brokering April 2013 + + +<!-- file-transfer-modes --> + + <xsd:complexType name="file-transfer-modesType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="file-transfer-mode" + minOccurs="0" maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + + <xsd:element name="file-transfer-modes" + type="file-transfer-modesType" /> + + <xsd:complexType name="file-transfer-modeType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute name="name" type="transfermode.datatype" + use="required" /> + <xsd:attribute name="package" type="xsd:string" use="required" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + <xsd:element name="file-transfer-mode" type="file-transfer-modeType" /> + + +<!-- asr-tts-support --> + +<xsd:complexType name="asr-tts-supportType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="asr-support" + minOccurs="0" maxOccurs="1" /> + <xsd:element ref="tts-support" + minOccurs="0" maxOccurs="1" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + + + +Boulton, et al. Standards Track [Page 100] + +RFC 6917 Media Resource Brokering April 2013 + + + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="asr-tts-support" type="asr-tts-supportType" /> + +<xsd:complexType name="asr-supportType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="language" + minOccurs="0" maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="asr-support" type="asr-supportType" /> + +<xsd:complexType name="tts-supportType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="language" + minOccurs="0" maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="tts-support" type="tts-supportType" /> + +<xsd:complexType name="languageType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute ref="xml:lang" /> + + + +Boulton, et al. Standards Track [Page 101] + +RFC 6917 Media Resource Brokering April 2013 + + + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="language" type="languageType" /> + + +<!-- media-server-location --> + +<xsd:complexType name="media-server-locationType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element name="civicAddress" type="ca:civicAddress" + minOccurs="1" maxOccurs="1" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + +<xsd:element name="media-server-location" + type="media-server-locationType" /> + + +<!-- vxml-support --> + + <xsd:complexType name="vxml-supportType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="vxml-mode" + minOccurs="0" maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + + <xsd:element name="vxml-support" type="vxml-supportType" /> + + + + + + +Boulton, et al. Standards Track [Page 102] + +RFC 6917 Media Resource Brokering April 2013 + + + <xsd:complexType name="vxml-modeType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute name="package" type="xsd:string" use="required" /> + <xsd:attribute name="support" type="vxml.datatype" use="required" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + + <xsd:element name="vxml-mode" type="vxml-modeType" /> + + +<!-- label --> + + <xsd:element name="label" type="label.datatype" /> + + +<!-- media-server-address --> + + <xsd:element name="media-server-address" type="xsd:anyURI" /> + +<!-- encryption --> + + <xsd:complexType name="encryptionType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + + <xsd:element name="encryption" type="encryptionType" /> + + + + + + + + + + +Boulton, et al. Standards Track [Page 103] + +RFC 6917 Media Resource Brokering April 2013 + + +<!-- + #################################################### + + DATATYPES + + #################################################### + --> + + <xsd:simpleType name="version.datatype"> + <xsd:restriction base="xsd:NMTOKEN"> + <xsd:enumeration value="1.0" /> + </xsd:restriction> + </xsd:simpleType> + +<xsd:simpleType name="id.datatype"> + <xsd:restriction base="xsd:NMTOKEN" /> + </xsd:simpleType> + + <xsd:simpleType name="status.datatype"> + <xsd:restriction base="xsd:positiveInteger"> + <xsd:pattern value="[0-9][0-9][0-9]" /> + </xsd:restriction> + </xsd:simpleType> + + <xsd:simpleType name="msstatus.datatype"> + <xsd:restriction base="xsd:NMTOKEN"> + <xsd:enumeration value="active" /> + <xsd:enumeration value="deactivated" /> + <xsd:enumeration value="unavailable" /> + </xsd:restriction> + </xsd:simpleType> + + <xsd:simpleType name="action.datatype"> + <xsd:restriction base="xsd:NMTOKEN"> + <xsd:enumeration value="create" /> + <xsd:enumeration value="update" /> + <xsd:enumeration value="remove" /> + </xsd:restriction> + </xsd:simpleType> + + <xsd:simpleType name="actions.datatype"> + <xsd:restriction base="xsd:NMTOKEN"> + <xsd:enumeration value="encoding" /> + <xsd:enumeration value="decoding" /> + <xsd:enumeration value="passthrough" /> + </xsd:restriction> + </xsd:simpleType> + + + + +Boulton, et al. Standards Track [Page 104] + +RFC 6917 Media Resource Brokering April 2013 + + + <xsd:simpleType name="appdata.datatype"> + <xsd:restriction base="xsd:string" /> + </xsd:simpleType> + + <xsd:simpleType name="dtmf.datatype"> + <xsd:restriction base="xsd:NMTOKEN"/> + </xsd:simpleType> + + <xsd:simpleType name="transfermode.datatype"> + <xsd:restriction base="xsd:NMTOKEN" /> + </xsd:simpleType> + + <xsd:simpleType name="boolean.datatype"> + <xsd:restriction base="xsd:NMTOKEN"> + <xsd:enumeration value="true" /> + <xsd:enumeration value="false" /> + </xsd:restriction> + </xsd:simpleType> + + <xsd:simpleType name="vxml.datatype"> + <xsd:restriction base="xsd:NMTOKEN"/> + </xsd:simpleType> + + <xsd:simpleType name="label.datatype"> + <xsd:restriction base="xsd:NMTOKEN" /> + </xsd:simpleType> + + <xsd:simpleType name="subscriptionid.datatype"> + <xsd:restriction base="xsd:NMTOKEN" /> + </xsd:simpleType> + +</xsd:schema> + + + + + + + + + + + + + + + + + + + +Boulton, et al. Standards Track [Page 105] + +RFC 6917 Media Resource Brokering April 2013 + + +11. Media Service Resource Consumer Interface XML Schema + + This section gives the XML Schema Definition + [W3C.REC-xmlschema-1-20041028] [W3C.REC-xmlschema-2-20041028] of the + "application/mrb-consumer+xml" format. + +<?xml version="1.0" encoding="UTF-8"?> +<xsd:schema targetNamespace="urn:ietf:params:xml:ns:mrb-consumer" + elementFormDefault="qualified" blockDefault="#all" + xmlns="urn:ietf:params:xml:ns:mrb-consumer" + xmlns:ca="urn:ietf:params:xml:ns:pidf:geopriv10:civicAddr" + xmlns:xsd="http://www.w3.org/2001/XMLSchema"> + + <xsd:annotation> + <xsd:documentation> + IETF MediaCtrl MRB 1.0 + + This is the schema of the IETF MediaCtrl MRB Consumer interface. + + The schema namespace is urn:ietf:params:xml:ns:mrb-consumer + + </xsd:documentation> + </xsd:annotation> + + + <!-- + ############################################################# + + SCHEMA IMPORTS + + ############################################################# + --> + + <xsd:import namespace="http://www.w3.org/XML/1998/namespace" + schemaLocation="http://www.w3.org/2001/xml.xsd"> + <xsd:annotation> + <xsd:documentation> + This import brings in the XML attributes for + xml:base, xml:lang, etc. + </xsd:documentation> + </xsd:annotation> + </xsd:import> + + <xsd:import + namespace="urn:ietf:params:xml:ns:pidf:geopriv10:civicAddr" + schemaLocation="civicAddress.xsd"> + <xsd:annotation> + <xsd:documentation> + + + +Boulton, et al. Standards Track [Page 106] + +RFC 6917 Media Resource Brokering April 2013 + + + This import brings in the civicAddress specification + from RFC 5139. + </xsd:documentation> + </xsd:annotation> + </xsd:import> + +<!-- + ##################################################### + + Extensible core type + + ##################################################### + --> + + <xsd:complexType name="Tcore"> + <xsd:annotation> + <xsd:documentation> + This type is extended by other (non-mixed) component types to + allow attributes from other namespaces. + </xsd:documentation> + </xsd:annotation> + <xsd:sequence/> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:complexType> + + +<!-- + ##################################################### + + TOP-LEVEL ELEMENT: mrbconsumer + + ##################################################### + --> + +<xsd:complexType name="mrbconsumerType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:choice> + <xsd:element ref="mediaResourceRequest" /> + <xsd:element ref="mediaResourceResponse" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:choice> + </xsd:sequence> + <xsd:attribute name="version" type="version.datatype" + use="required" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + + + +Boulton, et al. Standards Track [Page 107] + +RFC 6917 Media Resource Brokering April 2013 + + + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + + <xsd:element name="mrbconsumer" type="mrbconsumerType" /> + + +<!-- + ##################################################### + + mediaResourceRequest TYPE + + ##################################################### + --> + +<!-- mediaResourceRequest --> + + <xsd:complexType name="mediaResourceRequestType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="generalInfo" minOccurs="0" /> + <xsd:element ref="ivrInfo" minOccurs="0" /> + <xsd:element ref="mixerInfo" minOccurs="0" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute name="id" type="xsd:string" + use="required" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + + <xsd:element name="mediaResourceRequest" + type="mediaResourceRequestType" /> + + + + + + + + + + + + + + + +Boulton, et al. Standards Track [Page 108] + +RFC 6917 Media Resource Brokering April 2013 + + +<!-- + ##################################################### + + generalInfo TYPE + + ##################################################### +--> + +<!-- generalInfo --> + +<xsd:complexType name="generalInfoType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="session-info" minOccurs="0" /> + <xsd:element ref="packages" minOccurs="0" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + +<xsd:element name="generalInfo" type="generalInfoType" /> + + +<!-- session-info --> + +<xsd:complexType name="session-infoType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element name="session-id" type="id.datatype"/> + <xsd:element name="seq" type="xsd:nonNegativeInteger"/> + <xsd:element name="action" type="action.datatype"/> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + +<xsd:element name="session-info" type="session-infoType" /> + + + + + + +Boulton, et al. Standards Track [Page 109] + +RFC 6917 Media Resource Brokering April 2013 + + +<!-- packages --> + +<xsd:complexType name="packagesType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element name="package" type="xsd:string" minOccurs="0" + maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="packages" type="packagesType"/> + + +<!-- + ##################################################### + + ivrInfo TYPE + + ##################################################### +--> + +<!-- ivrInfo --> + +<xsd:complexType name="ivrInfoType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="ivr-sessions" minOccurs="0" /> + <xsd:element ref="file-formats" minOccurs="0" /> + <xsd:element ref="dtmf-type" minOccurs="0" /> + <xsd:element ref="tones" minOccurs="0" /> + <xsd:element ref="asr-tts" minOccurs="0" /> + <xsd:element ref="vxml" minOccurs="0" /> + <xsd:element ref="location" minOccurs="0" /> + <xsd:element ref="encryption" minOccurs="0" /> + <xsd:element ref="application-data" minOccurs="0" /> + <xsd:element ref="max-prepared-duration" minOccurs="0" /> + <xsd:element ref="file-transfer-modes" minOccurs="0" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + + + +Boulton, et al. Standards Track [Page 110] + +RFC 6917 Media Resource Brokering April 2013 + + + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + +<xsd:element name="ivrInfo" type="ivrInfoType" /> + + +<!-- + ##################################################### + + mixerInfo TYPE + + ##################################################### +--> + +<!-- mixerInfo --> + +<xsd:complexType name="mixerInfoType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="mixers" minOccurs="0"/> + <xsd:element ref="file-formats" minOccurs="0"/> + <xsd:element ref="dtmf-type" minOccurs="0"/> + <xsd:element ref="tones" minOccurs="0"/> + <xsd:element ref="mixing-modes" minOccurs="0"/> + <xsd:element ref="application-data" minOccurs="0"/> + <xsd:element ref="location" minOccurs="0"/> + <xsd:element ref="encryption" minOccurs="0"/> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + +<xsd:element name="mixerInfo" type="mixerInfoType" /> + + + + + + + + + + + + + +Boulton, et al. Standards Track [Page 111] + +RFC 6917 Media Resource Brokering April 2013 + + +<!-- + ##################################################### + + mediaResourceResponse TYPE + + ##################################################### + --> + +<!-- mediaResourceResponse --> + + <xsd:complexType name="mediaResourceResponseType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="response-session-info" minOccurs="0" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute name="id" type="xsd:string" + use="required" /> + <xsd:attribute name="status" type="status.datatype" + use="required" /> + <xsd:attribute name="reason" type="xsd:string" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + + <xsd:element name="mediaResourceResponse" + type="mediaResourceResponseType" /> + + +<!-- + #################################################### + + ELEMENTS + + #################################################### + --> + +<!-- response-session-info --> + +<xsd:complexType name="response-session-infoType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element name="session-id" type="id.datatype"/> + <xsd:element name="seq" type="xsd:nonNegativeInteger"/> + + + +Boulton, et al. Standards Track [Page 112] + +RFC 6917 Media Resource Brokering April 2013 + + + <xsd:element name="expires" type="xsd:nonNegativeInteger"/> + <xsd:element ref="media-server-address" + minOccurs="0" maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + +<xsd:element name="response-session-info" + type="response-session-infoType" /> + +<!-- media-server-address --> + +<xsd:complexType name="media-server-addressTYPE"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element name="connection-id" type="xsd:string" + minOccurs="0" maxOccurs="unbounded" /> + <xsd:element ref="ivr-sessions" minOccurs="0"/> + <xsd:element ref="mixers" minOccurs="0"/> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute name="uri" type="xsd:anyURI" use="required" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="media-server-address" + type="media-server-addressTYPE" /> + +<!-- ivr-sessions --> + +<xsd:complexType name="ivr-sessionsType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="rtp-codec" minOccurs="0" + maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + + + +Boulton, et al. Standards Track [Page 113] + +RFC 6917 Media Resource Brokering April 2013 + + + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + +<xsd:element name="ivr-sessions" type="ivr-sessionsType" /> + +<xsd:complexType name="rtp-codecType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element name="decoding" type="xsd:nonNegativeInteger" /> + <xsd:element name="encoding" type="xsd:nonNegativeInteger" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute name="name" type="xsd:string" use="required" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + +<xsd:element name="rtp-codec" type="rtp-codecType" /> + + +<!-- file-formats --> + +<xsd:complexType name="file-formatsType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="required-format" + minOccurs="0" maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="file-formats" type="file-formatsType" /> + +<xsd:complexType name="required-formatType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="required-file-package" + minOccurs="0" maxOccurs="unbounded" /> + + + +Boulton, et al. Standards Track [Page 114] + +RFC 6917 Media Resource Brokering April 2013 + + + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute name="name" type="xsd:string" use="required" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="required-format" type="required-formatType" /> + +<xsd:complexType name="required-file-packageType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element name="required-file-package-name" type="xsd:string" + minOccurs="0" maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="required-file-package" + type="required-file-packageType" /> + +<!-- dtmf-type --> + +<xsd:complexType name="dtmfType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="detect" /> + <xsd:element ref="generate" /> + <xsd:element ref="passthrough" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="dtmf" type="dtmfType" /> + +<xsd:complexType name="detectType"> + + + +Boulton, et al. Standards Track [Page 115] + +RFC 6917 Media Resource Brokering April 2013 + + + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="dtmf-type" + minOccurs="0" maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="detect" type="detectType" /> + +<xsd:complexType name="generateType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="dtmf-type" + minOccurs="0" maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="generate" type="generateType" /> + +<xsd:complexType name="passthroughType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="dtmf-type" + minOccurs="0" maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="passthrough" type="passthroughType" /> + +<xsd:complexType name="dtmf-typeType"> + + + +Boulton, et al. Standards Track [Page 116] + +RFC 6917 Media Resource Brokering April 2013 + + + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute name="name" type="dtmf.datatype" use="required" /> + <xsd:attribute name="package" type="xsd:string" use="required" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="dtmf-type" type="dtmf-typeType" /> + +<!-- tones --> + +<xsd:complexType name="required-tonesType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="country-codes" + minOccurs="0" maxOccurs="1" /> + <xsd:element ref="h248-codes" + minOccurs="0" maxOccurs="1" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="tones" type="required-tonesType" /> + +<xsd:complexType name="required-country-codesType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="country-code" + minOccurs="0" maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + + + +Boulton, et al. Standards Track [Page 117] + +RFC 6917 Media Resource Brokering April 2013 + + +<xsd:element name="country-codes" + type="required-country-codesType" /> + +<xsd:complexType name="country-codeType" mixed="true"> + <xsd:sequence> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute name="package" type="xsd:string" use="required" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> +</xsd:complexType> + +<xsd:element name="country-code" type="country-codeType" /> + +<xsd:complexType name="required-h248-codesType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="h248-code" + minOccurs="0" maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="h248-codes" + type="required-h248-codesType" /> + +<xsd:complexType name="h248-codeType" mixed="true"> + <xsd:sequence> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute name="package" type="xsd:string" use="required" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> +</xsd:complexType> + +<xsd:element name="h248-code" type="h248-codeType" /> + +<!-- asr-tts --> + +<xsd:complexType name="asr-ttsType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + + + +Boulton, et al. Standards Track [Page 118] + +RFC 6917 Media Resource Brokering April 2013 + + + <xsd:element ref="asr-support" + minOccurs="0" maxOccurs="1" /> + <xsd:element ref="tts-support" + minOccurs="0" maxOccurs="1" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="asr-tts" type="asr-ttsType" /> + +<xsd:complexType name="asr-supportType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="language" + minOccurs="0" maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="asr-support" type="asr-supportType" /> + +<xsd:complexType name="tts-supportType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="language" + minOccurs="0" maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="tts-support" type="tts-supportType" /> + +<xsd:complexType name="languageType"> + <xsd:complexContent> + + + +Boulton, et al. Standards Track [Page 119] + +RFC 6917 Media Resource Brokering April 2013 + + + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute ref="xml:lang" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="language" type="languageType" /> + + +<!-- vxml --> + +<xsd:complexType name="vxmlType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="vxml-mode" + minOccurs="0" maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="vxml" type="vxmlType" /> + +<xsd:complexType name="vxml-modeType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute name="package" type="xsd:string" use="required" /> + <xsd:attribute name="require" type="vxml.datatype" use="required" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="vxml-mode" type="vxml-modeType" /> + + + + +Boulton, et al. Standards Track [Page 120] + +RFC 6917 Media Resource Brokering April 2013 + + +<!-- location --> + +<xsd:complexType name="locationType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="ca:civicAddress" + minOccurs="1" maxOccurs="1" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + +<xsd:element name="location" type="locationType" /> + + +<!-- encryption --> + + <xsd:complexType name="encryptionType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + </xsd:complexType> + + <xsd:element name="encryption" type="encryptionType" /> + +<!-- application-data --> + +<xsd:element name="application-data" type="appdata.datatype" /> + +<!-- max-prepared-duration --> + +<xsd:complexType name="max-prepared-durationType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="max-time" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + + + +Boulton, et al. Standards Track [Page 121] + +RFC 6917 Media Resource Brokering April 2013 + + + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="max-prepared-duration" + type="max-prepared-durationType" /> + + +<xsd:complexType name="max-timeType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element name="max-time-package" type="xsd:string" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute name="max-time-seconds" type="xsd:nonNegativeInteger" + use="required" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="max-time" type="max-timeType" /> + + +<!-- file-transfer-modes --> + +<xsd:complexType name="file-transfer-modesType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="file-transfer-mode" + minOccurs="0" maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="file-transfer-modes" + type="file-transfer-modesType" /> + +<xsd:complexType name="file-transfer-modeType"> + + + +Boulton, et al. Standards Track [Page 122] + +RFC 6917 Media Resource Brokering April 2013 + + + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute name="name" type="transfermode.datatype" + use="required" /> + <xsd:attribute name="package" type="xsd:string" use="required" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="file-transfer-mode" type="file-transfer-modeType" /> + +<!-- mixers --> + +<xsd:complexType name="mixerssessionsType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="mix" minOccurs="0" + maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="mixers" type="mixerssessionsType" /> + +<xsd:complexType name="mixType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="rtp-codec" minOccurs="0" + maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute name="users" type="xsd:nonNegativeInteger" + use="required" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> + + + +Boulton, et al. Standards Track [Page 123] + +RFC 6917 Media Resource Brokering April 2013 + + +</xsd:complexType> + +<xsd:element name="mix" type="mixType" /> + +<!-- mixing-modes --> + +<xsd:complexType name="mixing-modesType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="audio-mixing-modes" + minOccurs="0" maxOccurs="1" /> + <xsd:element ref="video-mixing-modes" + minOccurs="0" maxOccurs="1" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="mixing-modes" type="mixing-modesType" /> + +<xsd:complexType name="audio-mixing-modesType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="audio-mixing-mode" + minOccurs="0" maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="audio-mixing-modes" type="audio-mixing-modesType" /> + +<xsd:complexType name="audio-mixing-modeType" mixed="true"> + <xsd:sequence> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute name="package" type="xsd:string" use="required" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> +</xsd:complexType> + + + +Boulton, et al. Standards Track [Page 124] + +RFC 6917 Media Resource Brokering April 2013 + + +<xsd:element name="audio-mixing-mode" type="audio-mixing-modeType" /> + +<xsd:complexType name="video-mixing-modesType"> + <xsd:complexContent> + <xsd:extension base="Tcore"> + <xsd:sequence> + <xsd:element ref="video-mixing-mode" + minOccurs="0" maxOccurs="unbounded" /> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute name="vas" type="boolean.datatype" + default="false" /> + <xsd:attribute name="activespeakermix" type="boolean.datatype" + default="false" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> + </xsd:extension> + </xsd:complexContent> +</xsd:complexType> + +<xsd:element name="video-mixing-modes" type="video-mixing-modesType" /> + +<xsd:complexType name="video-mixing-modeType" mixed="true"> + <xsd:sequence> + <xsd:any namespace="##other" minOccurs="0" + maxOccurs="unbounded" processContents="lax" /> + </xsd:sequence> + <xsd:attribute name="package" type="xsd:string" use="required" /> + <xsd:anyAttribute namespace="##other" processContents="lax" /> +</xsd:complexType> + +<xsd:element name="video-mixing-mode" type="video-mixing-modeType" /> + + +<!-- + #################################################### + + DATATYPES + + #################################################### + --> + +<xsd:simpleType name="version.datatype"> + <xsd:restriction base="xsd:NMTOKEN"> + <xsd:enumeration value="1.0" /> + </xsd:restriction> +</xsd:simpleType> + + + + +Boulton, et al. Standards Track [Page 125] + +RFC 6917 Media Resource Brokering April 2013 + + +<xsd:simpleType name="id.datatype"> + <xsd:restriction base="xsd:NMTOKEN" /> +</xsd:simpleType> + +<xsd:simpleType name="status.datatype"> + <xsd:restriction base="xsd:positiveInteger"> + <xsd:pattern value="[0-9][0-9][0-9]" /> + </xsd:restriction> +</xsd:simpleType> + +<xsd:simpleType name="transfermode.datatype"> + <xsd:restriction base="xsd:NMTOKEN"/> +</xsd:simpleType> + +<xsd:simpleType name="action.datatype"> + <xsd:restriction base="xsd:NMTOKEN"> + <xsd:enumeration value="remove" /> + <xsd:enumeration value="update" /> + </xsd:restriction> +</xsd:simpleType> + +<xsd:simpleType name="dtmf.datatype"> + <xsd:restriction base="xsd:NMTOKEN"/> +</xsd:simpleType> + +<xsd:simpleType name="boolean.datatype"> + <xsd:restriction base="xsd:NMTOKEN"> + <xsd:enumeration value="true" /> + <xsd:enumeration value="false" /> + </xsd:restriction> +</xsd:simpleType> + +<xsd:simpleType name="vxml.datatype"> + <xsd:restriction base="xsd:NMTOKEN"/> +</xsd:simpleType> + +<xsd:simpleType name="appdata.datatype"> + <xsd:restriction base="xsd:string" /> + </xsd:simpleType> + +</xsd:schema> + + + + + + + + + + +Boulton, et al. Standards Track [Page 126] + +RFC 6917 Media Resource Brokering April 2013 + + +12. Security Considerations + + The MRB network entity has two primary interfaces -- Publish and + Consumer -- that carry sensitive information and must therefore be + appropriately protected and secured. + + The Publish interface, as defined in and described in Section 5.1, + uses the Media Control Channel Framework [RFC6230] as a mechanism to + connect an MRB to a Media Server. It is very important that the + communication between the MRB and the Media Server is secured: a + malicious entity may change or even delete subscriptions to a Media + Server, thus affecting the view the MRB has of the resources actually + available on a Media Server, leading it to incorrect selection when + media resources are being requested by an Application Server. A + malicious entity may even manipulate available resources on a Media + Server, for example, to make the MRB think no resources are available + at all. Considering that the Publish interface is a CFW Control + Package, the same security considerations included in the Media + Control Channel Framework specification apply here to protect + interactions between an MRB and a Media Server. + + The Publish interface also allows a Media Server, as explained in + Section 5.1.5.18, to provide more or less accurate information about + its geographic location, should Application Servers be interested in + such details when looking for services at an MRB. While the usage of + this information is entirely optional and the level of detail to be + provided is implementation specific, it is important to draw + attention to the potential security issues that the disclosure of + such addresses may introduce. As such, it is important to make sure + MRB implementations don't disclose this information as is to + interested Application Servers but only exploit those addresses as + part of computation algorithms to pick the most adequate resources + Application Servers may be looking for. + + The Consumer interface, as defined in and described in Section 5.2, + conceives transactions based on a session ID. These transactions may + be transported either by means of HTTP messages or SIP dialogs. This + means that malicious users could be able to disrupt or manipulate an + MRB session should they have access to the above-mentioned session ID + or replicate it somehow: for instance, a malicious entity could + modify an existing session between an Application Server and the MRB, + e.g., requesting less resources than originally requested to cause + media dialogs to be rejected by the Application Server, or requesting + many more resources instead to try and lock as many of (if not all) + the resources an MRB can provide, thus making them unavailable to + other legitimate Application Servers in subsequent requests. In + order to prevent this, it is strongly advised that MRB + implementations generate session identifiers that are very hard to + + + +Boulton, et al. Standards Track [Page 127] + +RFC 6917 Media Resource Brokering April 2013 + + + replicate, in order to minimize the chances that malicious users + could gain access to valid identifiers by just guessing or by means + of brute-force attacks. It is very important, of course, to also + secure the way that these identifiers are transported by the involved + parties, in both requests and responses, in order to prevent network + attackers from intercepting Consumer messages and having access to + session IDs. The Consumer interface uses either the Hypertext + Transfer Protocol (HTTP) or the Session Initiation Protocol (SIP) as + the mechanism for clients to connect to an MRB to request media + resources. In the case where HTTP is used, any binding using the + Consumer interface MUST be capable of being transacted over Transport + Layer Security (TLS), as described in RFC 2818 [RFC2818]. In the + case where SIP is used, the same security considerations included in + the Media Control Channel Framework specification apply here to + protect interactions between a client requesting media resources and + an MRB. + + Should a valid session ID be compromised somehow (that is, + intercepted or just guessed by a malicious user), as a further means + to prevent disruption the Consumer interface also prescribes the use + of a sequence number in its transactions. This sequence number is to + be increased after each successful transaction, starting from a first + value randomly generated by the MRB when the session is first + created, and it must match in every request/response. While this + adds complexity to the protocol (implementations must pay attention + to those sequence numbers, since wrong values will cause "Wrong + sequence number" errors and the failure of the related requests), it + is an important added value for security. In fact, considering that + different transactions related to the same session could be + transported in different, unrelated HTTP messages (or SIP INVITEs in + cases where the In-line mode is being used), this sequence number + protection prevents the chances of session replication or disruption, + especially in cases where the session ID has been compromised: that + is, it should make it harder for malicious users to manipulate or + remove a session for which they have obtained the session ID. It is + strongly advised that the MRB doesn't choose 1 as the first sequence + number for a new session but rather picks a random value to start + from. The reaction to transactions that are out of sequence is left + to MRB implementations: a related error code is available, but + implementations may decide to enforce further limitations or actions + upon the receipt of too many failed attempts in a row or of what + looks like blatant attempts to guess what the current, valid sequence + number is. + + It is also worth noting that in In-line mode (both IAMM and IUMM) the + MRB may act as a Back-to-Back User Agent (B2BUA). This means that + when acting as a B2BUA the MRB may modify SIP bodies: it is the case, + for instance, for the IAMM handling multipart/mixed payloads. This + + + +Boulton, et al. Standards Track [Page 128] + +RFC 6917 Media Resource Brokering April 2013 + + + impacts the ability to use any SIP security feature that protects the + body (e.g., RFC 4474 [RFC4474], S/MIME, etc.), unless the MRB acts as + a mediator for the security association. This should be taken into + account when implementing an MRB compliant with this specification. + + Both the Publishing interface and Consumer interface may address the + location of a Media Server: the Publishing interface may be used to + inform the MRB where a Media Server is located (approximately or + precisely), and the Consumer interface may be used to ask for a Media + Server located somewhere in a particular region (e.g., a conference + bridge close to San Francisco). Both Media Server and MRB + implementers need to take this into account when deciding whether or + not to make this location information available, and if so how many + bits of information really need to be made available for brokering + purposes. + + It is worthwhile to cover authorization issues related to this + specification. Neither the Publishing interface nor the Consumer + interface provides an explicit means for implementing authentication, + i.e., they do not contain specific protocol interactions to ensure + that authorized Application Servers can make use of the services + provided by an MRB instance. Considering that both interfaces are + transported using well-established protocols (HTTP, SIP, CFW), + support for such functionality can be expressed by means of the + authentication mechanisms provided by the protocols themselves. + Therefore, any MRB-aware entity (Application Servers, Media Servers, + MRBs themselves) MUST support HTTP and SIP Digest access + authentication. The usage of such Digest access authentications is + recommended and not mandatory, which means MRB-aware entities MAY + exploit it in deployment. + + An MRB may want to enforce further constraints on the interactions + between an Application Server/Media Server and an MRB. For example, + it may choose to only accept requests associated with a specific + session ID from the IP address that originated the first request or + may just make use of pre-shared certificates to assess the identity + of legitimate Application Servers and/or Media Servers. + + + + + + + + + + + + + + +Boulton, et al. Standards Track [Page 129] + +RFC 6917 Media Resource Brokering April 2013 + + +13. IANA Considerations + + There are several IANA considerations associated with this + specification. + +13.1. Media Control Channel Framework Package Registration + + This section registers a new Media Control Channel Framework package, + per the instructions in Section 13.1 of [RFC6230]. + + Package Name: mrb-publish/1.0 + + Published Specification(s): RFC 6917 + + Person and email address to contact for further information: IETF + MediaCtrl working group (mediactrl@ietf.org), Chris Boulton + (chris@ns-technologies.com). + +13.2. application/mrb-publish+xml Media Type + + To: application + + Subject: Registration of media type application/mrb-publish+xml + + Type name: application + + Subtype name: mrb-publish+xml + + Required parameters: none + + Optional parameters: Same as charset parameter of application/xml as + specified in RFC 3023 [RFC3023]. + + Encoding considerations: Same as encoding considerations of + application/xml as specified in RFC 3023 [RFC3023]. + + Security considerations: See Section 10 of RFC 3023 [RFC3023] and + Section 12 of RFC 6917. + + Interoperability considerations: none. + + Published specification: Section 10 of RFC 6917. + + Applications that use this media type: This media type is used to + support a Media Resource Broker (MRB) entity. + + + + + + +Boulton, et al. Standards Track [Page 130] + +RFC 6917 Media Resource Brokering April 2013 + + + Additional Information: + + Magic Number: None + + File Extension: .xdf + + Macintosh file type code: "TEXT" + + Person and email address to contact for further information: Chris + Boulton (chris@ns-technologies.com). + + Intended usage: COMMON + + Author/Change controller: The IETF. + +13.3. application/mrb-consumer+xml Media Type + + To: application + + Subject: Registration of media type application/mrb-consumer+xml + + Type name: application + + Subtype name: mrb-consumer+xml + + Mandatory parameters: none + + Optional parameters: Same as charset parameter of application/xml as + specified in RFC 3023 [RFC3023]. + + Encoding considerations: Same as encoding considerations of + application/xml as specified in RFC 3023 [RFC3023]. + + Security considerations: See Section 10 of RFC 3023 [RFC3023] and + Section 12 of RFC 6917. + + Interoperability considerations: none. + + Published specification: Section 11 of RFC 6917. + + Applications that use this media type: This media type is used to + support a Media Resource Broker (MRB) entity. + + + + + + + + + +Boulton, et al. Standards Track [Page 131] + +RFC 6917 Media Resource Brokering April 2013 + + + Additional Information: + + Magic Number: None + + File Extension: .xdf + + Macintosh file type code: "TEXT" + + Person and email address to contact for further information: Chris + Boulton (chris@ns-technologies.com). + + Intended usage: COMMON + + Author/Change controller: The IETF. + +13.4. URN Sub-Namespace Registration for mrb-publish + + IANA has registered the URN "urn:ietf:params:xml:ns:mrb-publish", + with the ID of "mrb-publish". The schema of the XML namespace named + urn:ietf:params:xml:ns:mrb-publish is in Section 10. + +13.5. URN Sub-Namespace Registration for mrb-consumer + + IANA has registered the URN "urn:ietf:params:xml:ns:mrb-consumer", + with the ID of "mrb-consumer". The schema of the XML namespace named + urn:ietf:params:xml:ns:mrb-consumer is in Section 11. + +13.6. XML Schema Registration for mrb-publish + + IANA has registered the schema for mrb-publish: + + URI: urn:ietf:params:xml:schema:mrb-publish + + ID: mrb-publish + + Filename: mrb-publish + + Registrant Contact: IETF MediaCtrl working group + (mediactrl@ietf.org) + + Schema: The XML for the schema is in Section 10 of this document. + + + + + + + + + + +Boulton, et al. Standards Track [Page 132] + +RFC 6917 Media Resource Brokering April 2013 + + +13.7. XML Schema Registration for mrb-consumer + + Please register the schema for mrb-consumer: + + URI: urn:ietf:params:xml:schema:mrb-consumer + + ID: mrb-consumer + + Filename: mrb-consumer + + Registrant Contact: IETF MediaCtrl working group + (mediactrl@ietf.org) + + Schema: The XML for the schema is in Section 11 of this document. + +14. Acknowledgements + + The authors would like to thank the members of the Publish Interface + design team, who provided valuable input into this document. The + design team consisted of Adnan Saleem, Michael Trank, Victor + Paulsamy, Martin Dolly, and Scott McGlashan. The authors would also + like to thank John Dally, Bob Epley, Simon Romano, Henry Lum, + Christian Groves, and Jonathan Lennox for input into this + specification. + + Ben Campbell carried out the RAI expert review on an early version of + this specification and provided a great deal of invaluable input. + +15. References + +15.1. Normative References + + [ISO.10646.2012] + International Organization for Standardization, + "Information technology -- Universal Coded Character Set + (UCS)", ISO Standard 10646, 2012. + + [ISO.3166-1] + International Organization for Standardization, "Codes for + the representation of names of countries and their + subdivisions - Part 1: Country codes", ISO Standard + 3166-1:2006, 2006. + + [ISO.639.2002] + International Organization for Standardization, "Codes for + the representation of names of languages -- Part 1: + Alpha-2 code", ISO Standard 639, 2002. + + + + +Boulton, et al. Standards Track [Page 133] + +RFC 6917 Media Resource Brokering April 2013 + + + [ITU-T.Q.1950] + International Telecommunication Union, "Bearer independent + call bearer control protocol", ITU-T Recommendation + Q.1950, December 2002. + + [RFC2046] Freed, N. and N. Borenstein, "Multipurpose Internet Mail + Extensions (MIME) Part Two: Media Types", RFC 2046, + November 1996. + + [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate + Requirement Levels", BCP 14, RFC 2119, March 1997. + + [RFC2616] Fielding, R., Gettys, J., Mogul, J., Frystyk, H., + Masinter, L., Leach, P., and T. Berners-Lee, "Hypertext + Transfer Protocol -- HTTP/1.1", RFC 2616, June 1999. + + [RFC3023] Murata, M., St. Laurent, S., and D. Kohn, "XML Media + Types", RFC 3023, January 2001. + + [RFC3261] 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. + + [RFC3311] Rosenberg, J., "The Session Initiation Protocol (SIP) + UPDATE Method", RFC 3311, October 2002. + + [RFC3711] Baugher, M., McGrew, D., Naslund, M., Carrara, E., and K. + Norrman, "The Secure Real-time Transport Protocol (SRTP)", + RFC 3711, March 2004. + + [RFC5139] Thomson, M. and J. Winterbottom, "Revised Civic Location + Format for Presence Information Data Format Location + Object (PIDF-LO)", RFC 5139, February 2008. + + [RFC5763] Fischl, J., Tschofenig, H., and E. Rescorla, "Framework + for Establishing a Secure Real-time Transport Protocol + (SRTP) Security Context Using Datagram Transport Layer + Security (DTLS)", RFC 5763, May 2010. + + [W3C.REC-xmlschema-1-20041028] + Thompson, H., Beech, D., Maloney, M., and N. Mendelsohn, + "XML Schema Part 1: Structures Second Edition", World Wide + Web Consortium Recommendation REC-xmlschema-1-20041028, + October 2004, + <http://www.w3.org/TR/2004/REC-xmlschema-1-20041028>. + + + + + +Boulton, et al. Standards Track [Page 134] + +RFC 6917 Media Resource Brokering April 2013 + + + [W3C.REC-xmlschema-2-20041028] + Biron, P. and A. Malhotra, "XML Schema Part 2: Datatypes + Second Edition", World Wide Web Consortium + Recommendation REC-xmlschema-2-20041028, October 2004, + <http://www.w3.org/TR/2004/REC-xmlschema-2-20041028>. + +15.2. Informative References + + [RFC2818] Rescorla, E., "HTTP Over TLS", RFC 2818, May 2000. + + [RFC4240] Burger, E., Van Dyke, J., and A. Spitzer, "Basic Network + Media Services with SIP", RFC 4240, December 2005. + + [RFC4474] Peterson, J. and C. Jennings, "Enhancements for + Authenticated Identity Management in the Session + Initiation Protocol (SIP)", RFC 4474, August 2006. + + [RFC4733] Schulzrinne, H. and T. Taylor, "RTP Payload for DTMF + Digits, Telephony Tones, and Telephony Signals", RFC 4733, + December 2006. + + [RFC5022] Van Dyke, J., Burger, E., and A. Spitzer, "Media Server + Control Markup Language (MSCML) and Protocol", RFC 5022, + September 2007. + + [RFC5167] Dolly, M. and R. Even, "Media Server Control Protocol + Requirements", RFC 5167, March 2008. + + [RFC5552] Burke, D. and M. Scott, "SIP Interface to VoiceXML Media + Services", RFC 5552, May 2009. + + [RFC5567] Melanchuk, T., "An Architectural Framework for Media + Server Control", RFC 5567, June 2009. + + [RFC5707] Saleem, A., Xin, Y., and G. Sharratt, "Media Server Markup + Language (MSML)", RFC 5707, February 2010. + + [RFC6230] Boulton, C., Melanchuk, T., and S. McGlashan, "Media + Control Channel Framework", RFC 6230, May 2011. + + [RFC6231] McGlashan, S., Melanchuk, T., and C. Boulton, "An + Interactive Voice Response (IVR) Control Package for the + Media Control Channel Framework", RFC 6231, May 2011. + + [RFC6381] Gellens, R., Singer, D., and P. Frojdh, "The 'Codecs' and + 'Profiles' Parameters for "Bucket" Media Types", RFC 6381, + August 2011. + + + + +Boulton, et al. Standards Track [Page 135] + +RFC 6917 Media Resource Brokering April 2013 + + + [RFC6501] Novo, O., Camarillo, G., Morgan, D., and J. Urpalainen, + "Conference Information Data Model for Centralized + Conferencing (XCON)", RFC 6501, March 2012. + + [RFC6505] McGlashan, S., Melanchuk, T., and C. Boulton, "A Mixer + Control Package for the Media Control Channel Framework", + RFC 6505, March 2012. + +Authors' Addresses + + Chris Boulton + NS-Technologies + + EMail: chris@ns-technologies.com + + + Lorenzo Miniero + Meetecho + Via Carlo Poerio 89 + Napoli 80100 + Italy + + EMail: lorenzo@meetecho.com + + + Gary Munson + AT&T + 200 Laurel Avenue South + Middletown, New Jersey 07748 + USA + + EMail: gamunson@gmail.com + + + + + + + + + + + + + + + + + + + +Boulton, et al. Standards Track [Page 136] + |