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

"Roni Even" <> Wed, 01 August 2012 18:28 UTC

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From: Roni Even <>
To: 'Magnus Westerlund' <>
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Date: Wed, 01 Aug 2012 21:27:45 +0200
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Cc: "'mmusic (E-mail)'" <>
Subject: Re: [MMUSIC] Proposal for LS reply regarding RTCP bandwidth negotiation
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-----Original Message-----
From: Magnus Westerlund [] 
Sent: 01 August, 2012 8:01 PM
To: Roni Even
Cc: 'mmusic (E-mail)'
Subject: Re: [MMUSIC] Proposal for LS reply regarding RTCP bandwidth

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

RE: this was not clear to me from the text since you talk also about
increasing or decreasing the total bw.

> 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.

RE: maybe point in the answer to RFC3556 for this comment " Has any special
consideration been taken around the usage of RR or RS parameter values of 0
as specified in RFC3556"


Magnus Westerlund

Multimedia Technologies, Ericsson Research EAB/TVM
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