Re: [MMUSIC] Congestion control

Martin Thomson <martin.thomson@gmail.com> Tue, 11 June 2013 18:16 UTC

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Date: Tue, 11 Jun 2013 11:16:11 -0700
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From: Martin Thomson <martin.thomson@gmail.com>
To: Bernard Aboba <bernard_aboba@hotmail.com>
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Cc: "mmusic@ietf.org" <mmusic@ietf.org>, Cullen Jennings <fluffy@iii.ca>
Subject: Re: [MMUSIC] Congestion control
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On 11 June 2013 03:05, Bernard Aboba <bernard_aboba@hotmail.com> wrote:
> Also, earlier there was a discussion of using signaling vs. Magnus' codec operation point to control resolution, which in the case of spatial scaling would involve addition or removal of layers - and as I recall, signaling won.

I wasn't there for that discussion, but I can imagine that that
conclusion might have been not representative for a number of reasons.
 When you talk about "addition", then I believe that signaling is
necessary (unless that was already allowed in the session description
somehow).  However, removal isn't so clear cut.  "Removal" might be a
permanent thing, in which case, an argument could be made for
signaling.  Where "removal" is just stopping transmission due to
congestion (or other transient conditions), then I don't think that
that signaling is appropriate.

The objections to COP might also have been influenced by the IPR
declarations on the document.