[AVTCORE] RTP Simulcast proposal has been updated

Magnus Westerlund <magnus.westerlund@ericsson.com> Thu, 24 October 2013 07:20 UTC

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Date: Thu, 24 Oct 2013 09:21:00 +0200
From: Magnus Westerlund <magnus.westerlund@ericsson.com>
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Subject: [AVTCORE] RTP Simulcast proposal has been updated
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My co-authors and I have updated the proposal for how to do Simulcast in
RTP so that it supports Unified Plan for SDP. Thus we can support single
media source per media description with multiple simulcast encodings.
It also support multiple sources per media description for
broadcast/simulcast as well as "legacy" usages where the simulcast
encoding versions are distributed across different media descriptions in
SDP. Thus simulcast within one as well as using multiple RTP sessions
(and thus transports) are supported.

This update also focuses the SRCNAME SDES item proposal to the need of
simulcast. SRCNAME is used to identify the relationship between an SSRC
and the media source and particular encoding carried. To speed up
acquisition we are proposing an generic SDES item RTP Header extension
to enable inclusion of the SRCNAME item in RTP headers at startup.

The proposal consists of three I-Ds and we will discuss the general
signalling and setup/negotiation in MMUSIC and the SRCNAME and the
header extension is requested to be presented in AVTEXT WG.


Feedback much appreciated


Magnus Westerlund

Multimedia Technologies, Ericsson Research EAB/TVM
Ericsson AB                | Phone  +46 10 7148287
Färögatan 6                | Mobile +46 73 0949079
SE-164 80 Stockholm, Sweden| mailto: magnus.westerlund@ericsson.com