Re: [MMUSIC] Congestion controll

Martin Thomson <martin.thomson@gmail.com> Mon, 10 June 2013 16:52 UTC

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Date: Mon, 10 Jun 2013 09:52:34 -0700
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From: Martin Thomson <martin.thomson@gmail.com>
To: Cullen Jennings <fluffy@iii.ca>
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Cc: Flemming Andreasen <fandreas@cisco.com>, Ari Keranen <ari.keranen@ericsson.com>, "mmusic@ietf.org" <mmusic@ietf.org>
Subject: Re: [MMUSIC] Congestion controll
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On 7 June 2013 21:44, Cullen Jennings <fluffy@iii.ca> wrote:
>> It would appear to me that both Plan A and Plan B use signaling not just to control the envelope of acceptable configurations, but to determine what is actually being sent at a given moment.
>
> This is the part I strongly disagree with. I think both plan A and B allow any type of control that is acceptable in RTP / SDP for this including the use of RTCP. I can't see how plan A / B have anything to do with this.

I think that this is the part that is getting confused.  This is not a
complaint against plan A or B.  I suspect that this is instead a
(wholly valid) concern with the the idea of using a=imageattr for
*setting* resolutions, which limits the ability of a sender to react
to congestion signals.  I agree with Cullen that this is separable
from A/B discussions.