[MMUSIC] Comments on draft-westerlund-mmusic-max-ssrc-00

Flemming Andreasen <fandreas@cisco.com> Tue, 06 November 2012 03:07 UTC

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Date: Mon, 05 Nov 2012 22:07:19 -0500
From: Flemming Andreasen <fandreas@cisco.com>
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Cc: draft-westerlund-mmusic-max-ssrc@tool.ietf.org
Subject: [MMUSIC] Comments on draft-westerlund-mmusic-max-ssrc-00
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Hi

A few high-level questions/comments on this draft:

1) The draft concerns itself with resource constraints within a single 
media description, however in practice, limitations will often span 
media description boundaries due to use of shared resources. Why the 
limited scope ?

2) The draft only considers resource limitations in terms of codecs, 
however there are many other potential limiting factors to be considered 
(endpoint-wise and network-wise). For example, use of security 
mechanisms may impact what can be supported, the frequency with which 
packets are sent, etc. Why is the scope limited to only the codecs 
themselves ?

3) SDP Media Capabilities provide a general framework and partial 
solution to indicate resource constraints that span media descriptions. 
While it does not cover the specific issue being handled here (multiple 
instances of a given codec), it provides a more general framework that 
lends itself to 1) and 2) above. Any particular reason to not use this 
framework ?

Lastly, given the royalty-bearing IPR disclosure associated with the 
draft (please correct me if I misread this), I think it would be 
desirable to make a clear distinction between the problem to solve and 
the solution proposed to see if we can find a royalty-free approach.

Thanks

-- Flemming (as Individual)