MMUSIC Working Group C. Holmberg
Internet-Draft Ericsson
Updates: 3264 (if approved) H. Alvestrand
Intended status: Standards Track Google
Expires: July 31, 2015 C. Jennings
Cisco
January 27, 2015
Negotiating Media Multiplexing Using the Session Description Protocol
(SDP)
draft-ietf-mmusic-sdp-bundle-negotiation-16.txt
Abstract
This specification defines a new Session Description Protocol (SDP)
Grouping Framework extension, 'BUNDLE'. The extension can be used
with the SDP Offer/Answer mechanism to negotiate the usage of a
single address:port combination (BUNDLE address) for receiving media,
referred to as bundled media, associated with multiple SDP media
descriptions ("m=" lines).
To assist endpoints in negotiating the use of bundle this
specification defines a new SDP attribute, 'bundle-only', which can
be used to request that specific media is only used if bundled. This
specification also updates sections 5.1, 8.1 and 8.2 of RFC 3264 to
allow an answerer to assign a non-zero port value to an "m=" line in
an SDP answer, even if the "m=" line in the associated SDP offer
contained a zero port value.
There are multiple ways to correlate the bundled RTP packets with the
appropriate media descriptions. This specification defines a new
RTCP source description (SDES) item and a new RTP header extension
that provides an additional way to do this correlation by using them
to carry a value that associates the RTP/RTCP packets with a specific
media description.
Status of This Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
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Drafts is at http://datatracker.ietf.org/drafts/current/.
Holmberg, et al. Expires July 31, 2015 [Page 1]Internet-Draft Bundled media January 2015
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This Internet-Draft will expire on July 31, 2015.
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Table of Contents
1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 4
2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 5
3. Conventions . . . . . . . . . . . . . . . . . . . . . . . . . 6
4. Applicability Statement . . . . . . . . . . . . . . . . . . . 7
5. SDP Grouping Framework BUNDLE Extension . . . . . . . . . . . 7
5.1. General . . . . . . . . . . . . . . . . . . . . . . . . . 7
6. SDP 'bundle-only' Attribute . . . . . . . . . . . . . . . . . 7
6.1. General . . . . . . . . . . . . . . . . . . . . . . . . . 7
6.2. bundle-only . . . . . . . . . . . . . . . . . . . . . . . 8
7. SDP Information Considerations . . . . . . . . . . . . . . . 8
7.1. General . . . . . . . . . . . . . . . . . . . . . . . . . 8
7.2. Connection Data (c=) . . . . . . . . . . . . . . . . . . 9
7.3. Bandwidth (b=) . . . . . . . . . . . . . . . . . . . . . 9
7.4. Attributes (a=) . . . . . . . . . . . . . . . . . . . . . 9
8. SDP Offer/Answer Procedures . . . . . . . . . . . . . . . . . 9
8.1. General . . . . . . . . . . . . . . . . . . . . . . . . . 9
8.2. Generating the Initial SDP Offer . . . . . . . . . . . . 10
8.2.1. General . . . . . . . . . . . . . . . . . . . . . . . 10
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