Re: [rtcweb] draft-alvestrand-one-rtp-00.txt and profile

Colin Perkins <csp@csperkins.org> Mon, 22 August 2011 16:48 UTC

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From: Colin Perkins <csp@csperkins.org>
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Date: Mon, 22 Aug 2011 17:49:30 +0100
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To: Harald Alvestrand <harald@alvestrand.no>
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Subject: Re: [rtcweb] draft-alvestrand-one-rtp-00.txt and profile
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On 15 Aug 2011, at 09:33, Harald Alvestrand wrote:
> On 08/15/11 09:57, Christer Holmberg wrote:
>> 
>> There are discussions in other SDOs about using AVPF for video and AVP for audio,             within a session.
>>  
>> However, those discussions are not within the context of multiplex.
> I added the following text:
> 
> The reason for the requirement for systematic proto is that there are many combinations that don't make sense (for instance "RTP/AVPF" in one section and "RTP/SAVP" in another would make encryption and availability of TMMBR depend on the outcome of negotiation, which seems strange). The cases where combinations make sense (RTP/AVPF with UDP/FEC for instance) also usually require that separate RTP sessions be used. [[QUESTION IN DRAFT: Are there sensible combinations?]]
> 
> Makes sense?
>> 


The only combinations I can think of that make sense are RTP/AVP with RTP/AVPF, and RTP/SAVP with RTP/SAVPF. It's not clear why you'd bother though, since the AVPF variant behaves the same as the AVP variant if you don't use the feedback.

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