path: root/doc/rfc/rfc3936.txt

Network Working Group                                        K. Kompella
Request for Comments: 3936                              Juniper Networks
Updates: 3209, 2205                                              J. Lang
BCP: 96                                                  Rincon Networks
Category: Best Current Practice                             October 2004


   Procedures for Modifying the Resource reSerVation Protocol (RSVP)

Status of this Memo

   This document specifies an Internet Best Current Practices for the
   Internet Community, and requests discussion and suggestions for
   improvements.  Distribution of this memo is unlimited.

Copyright Notice

   Copyright (C) The Internet Society (2004).

Abstract

   This memo specifies procedures for modifying the Resource reSerVation
   Protocol (RSVP).  This memo also lays out new assignment guidelines
   for number spaces for RSVP messages, object classes, class-types, and
   sub-objects.

1.  Introduction

   This memo specifies procedures for modifying the Resource reSerVation
   Protocol (RSVP) [RSVP], including (but not limited to) adding,
   updating, extending or obsoleting: messages, message formats and
   procedures, object classes and class types, object formats and
   procedures; header formats, error codes and subcodes and semantics,
   and procedures for sending, receiving, and addressing RSVP messages.

   IANA recognizes the following RSVP name spaces: Message Types, Class
   Names, Class Numbers, Class Types and Sub-objects, Virtual
   Destination Ports, and Error Codes and (Subcode) Values (all of these
   will collectively be referred to as RSVP entities in this document).
   This memo specifies ranges for each name space and assignment
   policies for each range.  New RSVP name spaces must be defined in a
   Standards Track RFC which include guidelines for IANA assignments
   within the new name spaces.

   The assignment policies used in this document are: Standards Action
   (as defined in [IANA]), Expert Review, and Organization/Vendor
   Private (more simply, "Vendor Private"); the last two are defined in
   this document.  The intent of these assignment policies is to ensure



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   that extensions to RSVP receive adequate review before code-points
   are assigned, without being overly rigid.  Thus, if an extension is
   widely accepted and its ramifications are well understood, it may
   receive an assignment from the Standards Action space; however, if an
   extension is experimental in nature, it receives an assignment from
   the Expert Review space, and may, with maturity, move to Standards
   Track.  Assignments from the Vendor Private space are not reviewed,
   but there are mechanisms in place to ensure that these codepoints can
   co-exist in a network without harm.

   A standards body other than the IETF that wishes to obtain an
   assignment for an RSVP entity must decide from which type of
   name/number space they desire their assignment be made from, and then
   submit the appropriate documentation.  For example, if the assignment
   is to be made from a number space designated as Standards Action, a
   Standards Track RFC MUST be submitted in support of the request for
   assignment.

   This memo updates the IANA Considerations section (section 7) of
   [RSVP-TE], replacing the assignment policies stated there.

   Conventions used in this document

   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 BCP 14, RFC 2119
   [KEYWORDS].

2.  Assignment Policies for RSVP Entities

   For each of the RSVP name spaces identified by IANA, the space is
   divided into assignment ranges; the following terms are used in
   describing the procedures by which IANA assigns values: "Standards
   Action" (as defined in [IANA]), "Expert Review", and
   "Organization/Vendor Private", defined below.

   "Expert Review" ranges refer to values that are to be reviewed by an
   Expert designated by the IESG.  The code points from these ranges are
   typically used for experimental extensions; such assignments MUST be
   requested by Experimental RFCs that document their use and
   processing, and the actual assignments made during the IANA actions
   for the document.  Values from "Expert Review" ranges MUST be
   registered with IANA.

   "Organization/Vendor Private" ranges refer to values that are
   enterprise-specific; these MUST NOT be registered with IANA.  For
   Vendor Private values, the first 4-octet word of the data field MUST
   be an enterprise code [ENT] as registered with the IANA SMI Network



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   Management Private Enterprise Codes, and the rest of the data
   thereafter is for the private use of the registered enterprise.  (For
   each RSVP entity that has a Vendor Private range, it must be
   specified where exactly the data field starts; see below for
   examples.)  In this way, different enterprises, vendors, or Standards
   Development Organizations (SDOs) can use the same code point without
   fear of collision.

2.1.  Message Types

   A Message Type is an 8-bit number that identifies the function of the
   RSVP message.  Values from 0 through 239 are to be assigned by
   Standards Action.  Values from 240 through 255 are to be assigned by
   Expert Review.

2.2.  Class Names and Numbers

   Each class of data objects in an RSVP message is identified by an all
   upper-case Class Name and an 8-bit Class Number (also known as
   Class-Num or C-Num).  Class Numbers are divided broadly into three
   ranges (0-127, 128-191, and 192-255) determined by the two high-order
   bits of the Class-Num object (the 'b' below represents a bit).

   Note: the first 32-bit word of an Object whose Class-Num or Class-
   Type is from the Vendor Private range MUST be that vendor's SMI
   enterprise code in network octet order (these enterprise codes can be
   obtained from, and registered with, IANA).  An implementation
   encountering a Vendor Private object with an SMI enterprise code that
   it does not recognize MUST treat that object (and enclosing message)
   based on the Class-Num, as specified in [RSVP], section 3.10.

      o  Class-Num = 0bbbbbbb

         Class Numbers from 0 through 119 are to be assigned by
         Standards Action.  Class Numbers from 120 through 123 are to be
         assigned by Expert Review.  Class Numbers from 124 through 127
         are reserved for Vendor Private Use.

      o  Class-Num = 10bbbbbb

         Class Numbers from 128 through 183 are to be assigned by
         Standards Action.  Class Numbers from 184 through 187 are to be
         assigned by Expert Review.  Class Numbers from 188 through 191
         are reserved for Vendor Private Use.







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      o  Class-Num = 11bbbbbb

         Class Numbers from 192 through 247 are to be assigned by
         Standards Action.  Class Numbers from 248 through 251 are to be
         assigned by Expert Review.  Class Numbers from 252 through 255
         are reserved for Vendor Private Use.

2.3.  Class Types

   Within each object class there is an 8-bit Class Type (also known as
   a C-Type).  Class Types are scoped to a Class Number.  In general,
   the appropriateness of allowing assignments of Class Types through
   Expert Review or Vendor Private depends on the semantics of the Class
   Number itself.  Thus, any new Class Number definition must specify an
   appropriate IANA Considerations policy for assigning additional Class
   Type values.

   For Class Numbers that pre-date this document (specifically, 0, 1,
   3-25, 30-37, 42-45, 64, 65, 128-131, 161-165, 192-196, and 207), the
   default assignment policy for new Class Types is Standards Action,
   unless a Standards Track or Best Current Practice RFC supercedes
   this.

2.3.1.  Sub-objects

   Within an object, sub-objects may be defined, generally as a Type-
   Length-Value triple.  This memo defines the assignment policies for
   sub-objects of EXPLICIT_ROUTE and RECORD_ROUTE.  An RFC defining new
   sub-objects MUST state how IANA is to assign the sub-object Types.

   The EXPLICIT_ROUTE object [RSVP-TE] carries a variable length sub-
   object that is identified by a 7-bit Type field.  Types 0 through 119
   are to be assigned by Standards Action.  Types 120 through 123 are to
   be assigned by Expert Review.  Types 124 through 127 are to be
   reserved for Vendor Private Use.

   The RECORD_ROUTE object [RSVP-TE] carries a variable length sub-
   object that is identified by an 8-bit Type field.  Types 0 through
   191 are to be assigned by Standards Action.  Types 192 through 251
   are to be assigned by Expert Review.  Types 252 through 255 are to be
   reserved for Vendor Private Use.

   The first four octets of the sub-object contents of a Vendor Private
   sub-object of an EXPLICIT_ROUTE or RECORD_ROUTE object MUST be that
   vendor's SMI enterprise code in network octet order.






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2.4.  Virtual Destination Ports

   Virtual destination ports are described in [RSVP-IPSEC], which also
   specifies how IANA assignments are to be made.

2.5.  Error Codes and Values

   An Error Code is an 8-bit quantity that appears in an ERROR_SPEC
   object to broadly define an error condition.  With each Error Code
   there may be a 16-bit Error Value that further specifies the cause of
   the error.  Error Value may be globally defined, in which case the
   sub-code component is assigned by IANA.

   Error Code values from 0 through 239 are to be assigned by Standards
   Action.  Values from 240 through 251 are to be assigned by Expert
   Review.  Values from 252 through 255 are reserved for Vendor Private
   Use.  If the Error Code is for Vendor Private Use, the first four
   octets following the Error Value MUST be the vendor's SMI enterprise
   code in network octet order.

   Globally defined Error Values are assigned by Standards Action.

3.  Modifying RSVP Procedures

   RSVP entities have associated procedures describing when and how they
   are to be sent, received, processed, and responded to.  A change to a
   procedure that affects the processing of an RSVP entity that belongs
   to a range designated "Standards Action" MUST be documented in a
   Standards Track RFC.  A change to a procedure that affects the
   processing of an RSVP entity that belongs to a range designated
   "Expert Review" MUST be documented in an Experimental RFC.

4.  Acknowledgements

   Many thanks to Scott Bradner, who encouraged this project, and made
   several helpful comments and suggestions.

5.  Security Considerations

   It is hoped that the procedures outlined in this memo will ensure
   that changes made to RSVP will be better reviewed and thus more
   architecturally sound, thereby enhancing the security both of the
   protocol and of networks deploying it.

6.  IANA Considerations

   See section 2.




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7.  References

7.1.  Normative References

   [KEYWORDS]   Bradner, S., "Key words for use in RFCs to Indicate
                Requirement Levels", BCP 14, RFC 2119, March 1997.

   [RSVP]       Braden, R., Ed., Zhang, L., Berson, S., Herzog, S., and
                S. Jamin, "Resource ReSerVation Protocol (RSVP) --
                Version 1 Functional Specification", RFC 2205, September
                1997.

   [RSVP-TE]    Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan,
                V., and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP
                Tunnels", RFC 3209, December 2001.

7.2.  Informative References

   [ENT]        IANA PRIVATE ENTERPRISE NUMBERS,
                http://www.iana.org/assignments/enterprise-numbers

   [IANA]       Narten, T. and H. Alvestrand, "Guidelines for Writing an
                IANA Considerations Section in RFCs", BCP 26, RFC 2434,
                October 1998.

   [RSVP-IPSEC] Berger, L. and T. O'Malley, "RSVP Extensions for IPSEC
                Data Flows", RFC 2207, September 1997.

8.  Authors' Addresses

   Kireeti Kompella
   Juniper Networks
   1194 N. Mathilda Ave
   Sunnyvale, CA 94089 USA

   EMail:  kireeti@juniper.net


   Jonathan P. Lang
   Rincon Networks

   EMail:  jplang@ieee.org









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9.  Full Copyright Statement

   Copyright (C) The Internet Society (2004).

   This document is subject to the rights, licenses and restrictions
   contained in BCP 78, and except as set forth therein, the authors
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Acknowledgement

   Funding for the RFC Editor function is currently provided by the
   Internet Society.







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