Miscellaneous Capabilities Negotiation in the Session Description Protocol (SDP)

Approval announcement
Draft of message to be sent after approval:

From: The IESG <iesg-secretary@ietf.org>
To: IETF-Announce <ietf-announce@ietf.org>
Cc: RFC Editor <rfc-editor@rfc-editor.org>,
    mmusic mailing list <mmusic@ietf.org>,
    mmusic chair <mmusic-chairs@tools.ietf.org>
Subject: Protocol Action: 'Miscellaneous Capabilities Negotiation in the Session Description Protocol (SDP)' to Proposed Standard (draft-ietf-mmusic-sdp-miscellaneous-caps-07.txt)

The IESG has approved the following document:
- 'Miscellaneous Capabilities Negotiation in the Session Description
   Protocol (SDP)'
  (draft-ietf-mmusic-sdp-miscellaneous-caps-07.txt) as Proposed Standard

This document is the product of the Multiparty Multimedia Session Control
Working Group.

The IESG contact persons are Gonzalo Camarillo and Richard Barnes.

A URL of this Internet Draft is:

*Technical Summary*

SDP has been extended with a capability negotiation mechanism based on
SDP Offer/Answer, which allows endpoints to negotiate transport
protocols, attributes as well additional media-related capabilities.

This document extends the SDP capability negotiation framework to allow
endpoints to negotiate three additional SDP capabilities. In particular,
this document provides a mechanism to negotiate bandwidth ('b=' line),
connection data ('c=' line), and titles ('i=' line for each session or
media) in SDP.

*Working Group Summary*

The document was adopted as a WG item in March 2012 and is an external
and long-standing dependency for 3GPP. The mechanisms in the document
are fairly straightforward and did not receive a lot of discussion in
the WG subsequently, and a WGLC was issued on the -02 version of the
draft in October 2012. There were no major comments received but a chair
review let to minor updates in the document resulting in the -04 version
in March 2013. At this point, several people noted lack of clarity wrt
potential overlap with ICE (RFC 5245) resulting in a somewhat
controversial debate on the mailing list about what the WG had agreed to
work on and timeliness of feedback on documents that had already been
through WGLC. See threads in


The chairs and document authors have subsequently worked to address the
concerns. While there has been limited explicit feedback on the current
wording, we have requested feedback several times, and lastly in
http://www.ietf.org/mail-archive/web/mmusic/current/msg10962.html which
resulted in no further comments received. Consequently, we believe all
concerns have been addressed at this point.

*Document Quality*

There are currently no known implementations of the draft, however the
draft is a dependency for 3GPP, so future implementations are expected.

Earlier versions of the draft have been reviewed by a couple of WG
participants and the document shepherd has reviewed the last several
versions in detail. As noted above, the connection data capability part
of the document has received detailed feedback more recently as well.
The major contributors to these as well as earlier discussions are
listed in the Acknowledgements section of the document.


Document Shepherd: Flemming Andreasen
Responsible AD: Gonzalo Camarillo