Re: [Dart] draft-dart-dscp-rtp - way forward

Colin Perkins <csp@csperkins.org> Thu, 28 August 2014 20:27 UTC

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From: Colin Perkins <csp@csperkins.org>
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Date: Thu, 28 Aug 2014 21:27:01 +0100
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Cc: "Black, David" <david.black@emc.com>, "dart@ietf.org" <dart@ietf.org>
Subject: Re: [Dart] draft-dart-dscp-rtp - way forward
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On 28 Aug 2014, at 20:48, Ben Campbell <ben@nostrum.com> wrote:
> On Aug 28, 2014, at 2:41 PM, Black, David <david.black@emc.com> wrote:
>>>> The distinction between RTCP SR and RR isn't useful here. What you want to say is that an SSRC needs to use the same marking for the RTCP packets it sends as it uses for the RTP packets it sends. If it doesn’t send any RTP packets, it marks its RTCP packets with the marking it would use if it did send RTP.
>>> 
>>> That last bit concerns me a bit. Are we really asking an implementation to figure out how it would have done something it isn’t going to do?
>> 
>> Yes, --David
> 
> Maybe I'm not connecting the dots correctly, but what kind of media is it going to not send? Are we assuming the same as what it receives?

Yes, that’s how RTP works. 

-- 
Colin Perkins
http://csperkins.org/