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Signaling Media Decoding Dependency in the Session Description Protocol (SDP)
RFC 5583

Revision differences

Document history

Date Rev. By Action
2018-12-20
08 (System)
Received changes through RFC Editor sync (changed abstract to 'This memo defines semantics that allow for signaling the decoding dependency of different media descriptions with …
Received changes through RFC Editor sync (changed abstract to 'This memo defines semantics that allow for signaling the decoding dependency of different media descriptions with the same media type in the Session Description Protocol (SDP). This is required, for example, if media data is separated and transported in different network streams as a result of the use of a layered or multiple descriptive media coding process.

A new grouping type "DDP" -- decoding dependency -- is defined, to be used in conjunction with RFC 3388 entitled "Grouping of Media Lines in the Session Description Protocol". In addition, an attribute is specified describing the relationship of the media streams in a "DDP" group indicated by media identification attribute(s) and media format description(s). [STANDARDS-TRACK]')
2016-11-30
08 (System) Closed request for Last Call review by SECDIR with state 'Unknown'
2015-10-14
08 (System) Notify list changed from mmusic-chairs@ietf.org, draft-ietf-mmusic-decoding-dependency@ietf.org to (None)
2012-08-22
08 (System) post-migration administrative database adjustment to the No Objection position for Magnus Westerlund
2012-08-22
08 (System) post-migration administrative database adjustment to the No Objection position for Russ Housley
2009-07-08
08 Cindy Morgan State Changes to RFC Published from RFC Ed Queue by Cindy Morgan
2009-07-08
08 Cindy Morgan [Note]: 'RFC 5583' added by Cindy Morgan
2009-07-07
08 (System) RFC published
2009-06-02
08 (System) IANA Action state changed to RFC-Ed-Ack from Waiting on RFC Editor
2009-06-02
08 (System) IANA Action state changed to Waiting on RFC Editor from In Progress
2009-06-02
08 (System) IANA Action state changed to In Progress from Waiting on Authors
2009-05-28
08 (System) IANA Action state changed to Waiting on Authors from In Progress
2009-05-28
08 Cindy Morgan State Changes to RFC Ed Queue from Approved-announcement sent by Cindy Morgan
2009-05-28
08 (System) IANA Action state changed to In Progress
2009-05-28
08 Cindy Morgan IESG state changed to Approved-announcement sent
2009-05-28
08 Cindy Morgan IESG has approved the document
2009-05-28
08 Cindy Morgan Closed "Approve" ballot
2009-05-28
08 Tim Polk [Ballot Position Update] New position, No Objection, has been recorded by Tim Polk
2009-05-22
08 Cullen Jennings State Changes to IESG Evaluation::AD Followup from IESG Evaluation by Cullen Jennings
2009-05-19
08 Cullen Jennings State Changes to IESG Evaluation from Approved-announcement to be sent by Cullen Jennings
2009-05-19
08 Amy Vezza State Changes to Approved-announcement to be sent from IESG Evaluation::AD Followup by Amy Vezza
2009-04-03
08 Magnus Westerlund [Ballot Position Update] Position for Magnus Westerlund has been changed to No Objection from Discuss by Magnus Westerlund
2009-04-03
08 (System) New version available: draft-ietf-mmusic-decoding-dependency-08.txt
2009-04-02
08 Magnus Westerlund
[Ballot discuss]
Section 8:

  The following semantics have been registered by IANA in Semantics for
  the "depend" SDP Attribute under SDP Parameters:

  …
[Ballot discuss]
Section 8:

  The following semantics have been registered by IANA in Semantics for
  the "depend" SDP Attribute under SDP Parameters:

  Semantics of the "depend" SDP attribute:

  Semantics                                Token    Reference
  ----------------------------            -----    ---------
  Layered decoding dependency              lay      RFC XXXX
  Multi descriptive decoding dependency    mdc      RFC XXXX

This registry lacks definition! Please provide registration rules for it.
2009-04-02
08 Magnus Westerlund [Ballot Position Update] Position for Magnus Westerlund has been changed to Discuss from No Objection by Magnus Westerlund
2009-04-02
08 Magnus Westerlund [Ballot Position Update] Position for Magnus Westerlund has been changed to No Objection from Discuss by Magnus Westerlund
2009-04-02
08 (System) Sub state has been changed to AD Follow up from New Id Needed
2009-04-02
07 (System) New version available: draft-ietf-mmusic-decoding-dependency-07.txt
2009-03-10
08 Magnus Westerlund
[Ballot discuss]
Section 6.1:

I am missing a clarification what the meaning of a=depend is in the cases with offers with send-only, sendrecv and recvonly. …
[Ballot discuss]
Section 6.1:

I am missing a clarification what the meaning of a=depend is in the cases with offers with send-only, sendrecv and recvonly. It is not clear from section 5.2.2 that a=depend applies to received media or sent media. Based on that how too layer things usually are a sender configuration, this clashes with offer/answer. Please clarify this relation ship.

I think a specific offer/answer example will also be warranted as soon as the mechanism has been worked out.

Section 8:

  The following semantics have been registered by IANA in Semantics for
  the "depend" SDP Attribute under SDP Parameters:

  Semantics of the "depend" SDP attribute:

  Semantics                                Token    Reference
  ----------------------------            -----    ---------
  Layered decoding dependency              lay      RFC XXXX
  Multi descriptive decoding dependency    mdc      RFC XXXX

This registry lacks definition! Please provide registration rules for it.
2009-02-27
08 (System) Removed from agenda for telechat - 2009-02-26
2009-02-26
08 Amy Vezza State Changes to IESG Evaluation::Revised ID Needed from IESG Evaluation by Amy Vezza
2009-02-26
08 Ross Callon [Ballot Position Update] New position, No Objection, has been recorded by Ross Callon
2009-02-26
08 Magnus Westerlund
[Ballot discuss]
Section 5.2.2:

  The depend-attribute describes the decoding dependency.  The depend-
  attribute MUST be followed by a sequence of dependent-fmt and the …
[Ballot discuss]
Section 5.2.2:

  The depend-attribute describes the decoding dependency.  The depend-
  attribute MUST be followed by a sequence of dependent-fmt and the
  corresponding dependency-tag fields which identify all related media
  format descriptions in all related media descriptions of the
  dependent-fmt.
 
The ABNF allows one to include no related media format descriptions. Can you please clarify the meaning of that. It seems that the dependency type overrules that possibility in some cases. Maybe that should be made explicit.

Section 6.1:

I am missing a clarification what the meaning of a=depend is in the cases with offers with send-only, sendrecv and recvonly. It is not clear from section 5.2.2 that a=depend applies to received media or sent media. Based on that how too layer things usually are a sender configuration, this clashes with offer/answer. Please clarify this relation ship.

I think a specific offer/answer example will also be warranted as soon as the mechanism has been worked out.

Section 8:

  The following semantics have been registered by IANA in Semantics for
  the "depend" SDP Attribute under SDP Parameters:

  Semantics of the "depend" SDP attribute:

  Semantics                                Token    Reference
  ----------------------------            -----    ---------
  Layered decoding dependency              lay      RFC XXXX
  Multi descriptive decoding dependency    mdc      RFC XXXX

This registry lacks definition! Please provide registration rules for it.
2009-02-26
08 Magnus Westerlund [Ballot Position Update] New position, Discuss, has been recorded by Magnus Westerlund
2009-02-26
08 Russ Housley [Ballot Position Update] Position for Russ Housley has been changed to No Objection from Discuss by Russ Housley
2009-02-26
08 Dan Romascanu [Ballot Position Update] New position, No Objection, has been recorded by Dan Romascanu
2009-02-26
08 Pasi Eronen [Ballot Position Update] New position, No Objection, has been recorded by Pasi Eronen
2009-02-26
08 Jon Peterson [Ballot Position Update] New position, No Objection, has been recorded by Jon Peterson
2009-02-25
08 Chris Newman [Ballot Position Update] New position, No Objection, has been recorded by Chris Newman
2009-02-25
08 Lisa Dusseault [Ballot Position Update] New position, No Objection, has been recorded by Lisa Dusseault
2009-02-25
08 Russ Housley
[Ballot discuss]
The Gen-ART Review by Brian Carpenter on 2-Feb-2009 lead to some
  discussion; however, at the end the authors asked "the MMUSIC chairs …
[Ballot discuss]
The Gen-ART Review by Brian Carpenter on 2-Feb-2009 lead to some
  discussion; however, at the end the authors asked "the MMUSIC chairs
  and Cullen for guidance."  As best I can tell, that guidance has not
  been provided.
2009-02-25
08 Russ Housley [Ballot Position Update] New position, Discuss, has been recorded by Russ Housley
2009-02-25
08 Mark Townsley [Ballot Position Update] New position, No Objection, has been recorded by Mark Townsley
2009-02-25
08 Jari Arkko [Ballot Position Update] New position, No Objection, has been recorded by Jari Arkko
2009-02-24
08 Ron Bonica [Ballot Position Update] New position, No Objection, has been recorded by Ron Bonica
2009-02-24
08 David Ward [Ballot Position Update] New position, No Objection, has been recorded by David Ward
2009-02-23
08 Cullen Jennings Note field has been cleared by Cullen Jennings
2009-02-23
08 Cullen Jennings Placed on agenda for telechat - 2009-02-26 by Cullen Jennings
2009-02-23
08 Cullen Jennings State Changes to IESG Evaluation from Waiting for AD Go-Ahead::AD Followup by Cullen Jennings
2009-02-23
08 Cullen Jennings [Ballot Position Update] New position, Yes, has been recorded for Cullen Jennings
2009-02-23
08 Cullen Jennings Ballot has been issued by Cullen Jennings
2009-02-23
08 Cullen Jennings Created "Approve" ballot
2009-02-23
08 (System) Sub state has been changed to AD Follow up from New Id Needed
2009-02-23
06 (System) New version available: draft-ietf-mmusic-decoding-dependency-06.txt
2009-02-20
08 Cullen Jennings [Note]: 'waiting for update or RFC Ed note.' added by Cullen Jennings
2009-02-20
08 Cullen Jennings State Changes to Waiting for AD Go-Ahead::Revised ID Needed from Waiting for AD Go-Ahead by Cullen Jennings
2009-02-20
08 Cullen Jennings [Note]: 'wating for update or RFC Ed note.' added by Cullen Jennings
2009-02-09
08 (System) State has been changed to Waiting for AD Go-Ahead from In Last Call by system
2009-02-05
08 Amanda Baber
IANA Last Call questions/comments:

QUESTION: What is the registration procedure for the
"depend" SDP Attribute values registry (Action #3)?

Action #1:

Upon approval of this …
IANA Last Call questions/comments:

QUESTION: What is the registration procedure for the
"depend" SDP Attribute values registry (Action #3)?

Action #1:

Upon approval of this document, IANA will make the following
assignment in the "Semantics for the 'group' SDP Attribute"
registry at
http://www.iana.org/assignments/sdp-parameters

Semantics Token Reference
------------------- ----- ---------
Decoding Dependency DDP [RFC-mmusic-decoding-dependency-05]


Action #2:

Upon approval of this document, IANA will make the following
assignment in the "att-field (media level only)" registry at
http://www.iana.org/assignments/sdp-parameters

Type SDP Name Reference
---- ------------------ ---------
depend [RFC-mmusic-decoding-dependency-05]


Action #3:

Upon approval of this document, IANA will create the following
registry at
http://www.iana.org/assignments/sdp-parameters

Registry Name: "depend" SDP Attribute values
Registration Procedures: ??

Initial contents of this sub-registry will be:

Token | Semantics | Reference
----- | ---------------------------- ----- ---------
lay | Layered decoding dependency | [RFC-mmusic-decoding-dependency-05]
mdc | Multi descriptive decoding dependency | [RFC-mmusic-decoding-dependency-05]

We understand the above to be the only IANA Actions for this document.
2009-02-01
08 Samuel Weiler Request for Last Call review by SECDIR is assigned to Radia Perlman
2009-02-01
08 Samuel Weiler Request for Last Call review by SECDIR is assigned to Radia Perlman
2009-01-26
08 Amy Vezza Last call sent
2009-01-26
08 Amy Vezza State Changes to In Last Call from Last Call Requested by Amy Vezza
2009-01-24
08 Cullen Jennings Last Call was requested by Cullen Jennings
2009-01-24
08 Cullen Jennings State Changes to Last Call Requested from AD Evaluation::External Party by Cullen Jennings
2009-01-24
08 (System) Ballot writeup text was added
2009-01-24
08 (System) Last call text was added
2009-01-24
08 (System) Ballot approval text was added
2008-11-20
05 (System) New version available: draft-ietf-mmusic-decoding-dependency-05.txt
2008-11-14
08 Cullen Jennings State Changes to AD Evaluation::External Party from AD Evaluation by Cullen Jennings
2008-11-13
08 Cullen Jennings State Changes to AD Evaluation from Publication Requested by Cullen Jennings
2008-10-30
08 Cindy Morgan
Requested Publication Status: Proposed Standard
PROTO shepherd: Joerg Ott (MMUSIC WG Co-Chair)

---------------------------------------------------------------------------

    (1.a) Who is the Document Shepherd for this document? Has …
Requested Publication Status: Proposed Standard
PROTO shepherd: Joerg Ott (MMUSIC WG Co-Chair)

---------------------------------------------------------------------------

    (1.a) Who is the Document Shepherd for this document? Has the
          Document Shepherd personally reviewed this version of the
          document and, in particular, does he or she believe this
          version is ready for forwarding to the IESG for publication?

    The document shepherd is Joerg Ott <jo@netlab.tkk.fi>, co-chair
    of the MMUSIC WG.

    I have personally reviewed this document and consider it ready
    for publication.  Besides the textual review, the ID nits tool
    has not found any issues and the contained ABNF compiles.

    (1.b) Has the document had adequate review both from key WG members
          and from key non-WG members? Does the Document Shepherd have
          any concerns about the depth or breadth of the reviews that
          have been performed?

    The draft has received ample discussion based upon repeated solid
    reviews over the last year and has been subject to repeated
    discussion in the WG meetings.  The breadth and depth of the
    reviews were adequate.  Detailed comments were raised during
    the first of two working group last calls and addressed by
    the authors.

    (1.c) Does the Document Shepherd have concerns that the document
          needs more review from a particular or broader perspective,
          e.g., security, operational complexity, someone familiar with
          AAA, internationalization or XML?

    No.  The draft expands on SDP for which MMUSIC is the responsible
    WG.  It is related to media encodings and RTP for which close
    interaction has happened with the appropriate people of the
    AVT WG.

    (1.d) Does the Document Shepherd have any specific concerns or
          issues with this document that the Responsible Area Director
          and/or the IESG should be aware of? For example, perhaps he
          or she is uncomfortable with certain parts of the document, or
          has concerns whether there really is a need for it. In any
          event, if the WG has discussed those issues and has indicated
          that it still wishes to advance the document, detail those
          concerns here. Has an IPR disclosure related to this document
          been filed? If so, please include a reference to the
          disclosure and summarize the WG discussion and conclusion on
          this issue.

    No concerns.  No IPR disclosures filed.

    (1.e) How solid is the WG consensus behind this document? Does it
          represent the strong concurrence of a few individuals, with
          others being silent, or does the WG as a whole understand and
          agree with it?

    The draft has undergone two Working Group Last Calls (on -02 and -03)
    and the comments received were incorporated into the draft.  There
    is solid consensus inside the WG for publication.

    (1.f) Has anyone threatened an appeal or otherwise indicated extreme
          discontent? If so, please summarise the areas of conflict in
          separate email messages to the Responsible Area Director. (It
          should be in a separate email because this questionnaire is
          entered into the ID Tracker.)

    No.

    (1.g) Has the Document Shepherd personally verified that the
          document satisfies all ID nits? (See
          http://www.ietf.org/ID-Checklist.html and
          http://tools.ietf.org/tools/idnits/). Boilerplate checks are
          not enough; this check needs to be thorough. Has the document
          met all formal review criteria it needs to, such as the MIB
          Doctor, media type and URI type reviews?

    Yes.  All checks pass.

    (1.h) Has the document split its references into normative and
          informative? Are there normative references to documents that
          are not ready for advancement or are otherwise in an unclear
          state? If such normative references exist, what is the
          strategy for their completion? Are there normative references
          that are downward references, as described in [RFC3967]? If
          so, list these downward references to support the Area
          Director in the Last Call procedure for them [RFC3967].

    Yes, the references are split.
    No, there are no dependencies on incomplete documents.

    (1.i) Has the Document Shepherd verified that the document IANA
          consideration section exists and is consistent with the body
          of the document? If the document specifies protocol
          extensions, are reservations requested in appropriate IANA
          registries? Are the IANA registries clearly identified? If
          the document creates a new registry, does it define the
          proposed initial contents of the registry and an allocation
          procedure for future registrations? Does it suggest a
          reasonable name for the new registry? See [RFC5226]. If the
          document describes an Expert Review process has Shepherd
          conferred with the Responsible Area Director so that the IESG
          can appoint the needed Expert during the IESG Evaluation?

    Yes, the IANA section exists, matches the content of the document,
    and clearly identifies the action and target contacts.

    (1.j) Has the Document Shepherd verified that sections of the
          document that are written in a formal language, such as XML
          code, BNF rules, MIB definitions, etc., validate correctly in
          an automated checker?

    The definitions are short (ABNF) but the checker is currently
    not reachable (tried for two days).

    (1.k) The IESG approval announcement includes a Document
          Announcement Write-Up. Please provide such a Document
          Announcement Write-Up? Recent examples can be found in the
          "Action" announcements for approved documents. The approval
          announcement contains the following sections:
          Technical Summary
              Relevant content can frequently be found in the abstract
              and/or introduction of the document. If not, this may be
              an indication that there are deficiencies in the abstract
              or introduction.
          Working Group Summary
              Was there anything in WG process that is worth noting? For
              example, was there controversy about particular points or
              were there decisions where the consensus was particularly
              rough?
          Document Quality
              Are there existing implementations of the protocol? Have a
              significant number of vendors indicated their plan to
              implement the specification? Are there any reviewers that
              merit special mention as having done a thorough review,
              e.g., one that resulted in important changes or a
              conclusion that the document had no substantive issues? If
              there was a MIB Doctor, Media Type or other expert review,
              what was its course (briefly)? In the case of a Media Type
              review, on what date was the request posted?

    Proposed announcment text:

    Technical summary:

        The document defines extensions to the Session Description
Protocol to explicitly specify dependencies between different
media streams to support advance media coding schemes, such
as multiple description coding and layered coding..

    Working Group summary:

        The MMUSIC WG has firm consenses on publishing this document
as Proposed Standard.

    Document quality:

    The document has received ample review and gone through two
working group last calls.  It is technically sound and stable.

    Personnel:

        The document shepherd is Joerg Ott, the responsible AD is
Cullen Jennings.
2008-10-30
08 Cindy Morgan Draft Added by Cindy Morgan in state Publication Requested
2008-10-21
04 (System) New version available: draft-ietf-mmusic-decoding-dependency-04.txt
2008-09-25
03 (System) New version available: draft-ietf-mmusic-decoding-dependency-03.txt
2008-05-23
02 (System) New version available: draft-ietf-mmusic-decoding-dependency-02.txt
2008-02-25
01 (System) New version available: draft-ietf-mmusic-decoding-dependency-01.txt
2007-12-03
00 (System) New version available: draft-ietf-mmusic-decoding-dependency-00.txt