Re: [MMUSIC] Congestion controll

Martin Thomson <martin.thomson@gmail.com> Mon, 10 June 2013 17:19 UTC

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Date: Mon, 10 Jun 2013 10:19:22 -0700
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From: Martin Thomson <martin.thomson@gmail.com>
To: Emil Ivov <emcho@jitsi.org>
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Cc: Flemming Andreasen <fandreas@cisco.com>, Ari Keranen <ari.keranen@ericsson.com>, "mmusic@ietf.org" <mmusic@ietf.org>, Cullen Jennings <fluffy@iii.ca>
Subject: Re: [MMUSIC] Congestion controll
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On 10 June 2013 10:10, Emil Ivov <emcho@jitsi.org> wrote:
>> I think that this is the part that is getting confused.  This is not a
>> complaint against plan A or B.
>
> It is indeed a problem with both of them and it is also mentioned in the No
> Plan draft.

Well then you've assumed something about Plan A/B that is incorrect.
Neither plan constrains usage in a way that would prevent senders from
responding to congestion signals.  The fine-grained control that you
report as being problematic doesn't prevent senders from sending fewer
bits.

Is it possible that you have assumed that the existence of an m-line
or a=ssrc implies that the sender is obligated to send?  It doesn't.

The only possible problem is the use of a=imageattr in the examples of
Plan B, which might (might) overconstrain a sender, but Plan B doesn't
mandate anything regarding that in text.  Assuming anything there
would be a real stretch.