Re: [MMUSIC] Proposal for LS reply regarding RTCP bandwidth negotiation

Magnus Westerlund <> Wed, 01 August 2012 18:01 UTC

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Date: Wed, 01 Aug 2012 11:01:20 -0700
From: Magnus Westerlund <>
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To: Roni Even <>
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Subject: Re: [MMUSIC] Proposal for LS reply regarding RTCP bandwidth negotiation
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On 2012-08-01 11:50, Roni Even wrote:
> Hi,
> The liaison looks OK to me.
> I agree with using option B in the first comment and to allow increasing BW
> in the answer. 
> As for comment 2 I assume that you are saying that the tradeoffs between
> increasing RTCP and reducing RTP bw using same session bw, or increasing the
> total session bw can be used to provide more RTCP bw with or without chaning
> RTP bw. These options should be documented.

I wanted to point out that you can allow increasing the value in a
response without affecting the total bandwidth as that is likely a
concern for the offerer.

> On the RR and SR value 0 are you suggesting to change RFC 3556.  I am not
> sure it is a good question to ask 3GPP if they did not mention it
> themselves; I am not supportive of the topic of negotiation of the use of
> RTCP. So suggest to remove this comment

I don't quite understand what you are trying to say. My intention was to
try to request that it is clarified about the usage of 0. So if I offer
a non-zero value are the answer really allowed to turn off RTCP? The
3GPP proposal do allow for turning off RTCP as proposed.


Magnus Westerlund

Multimedia Technologies, Ericsson Research EAB/TVM
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