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RE: Mapping of media streams to RTP (Re: Query: What does "context" mean in the context (sic) of requirement A15? [ACTION-6])

From: Elwell, John <john.elwell@siemens-enterprise.com>
Date: Thu, 25 Aug 2011 09:50:53 +0200
To: Randell Jesup <randell-ietf@jesup.org>, "public-webrtc@w3.org" <public-webrtc@w3.org>
Message-ID: <A444A0F8084434499206E78C106220CA0B00FDB9E3@MCHP058A.global-ad.net>
Randell,

Good point - if the first RTCP packet gets dropped, it will be a long time before the next one arrives, and in the meantime no CSRC to SSRC mapping will be available. 

John

John Elwell
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> -----Original Message-----
> From: public-webrtc-request@w3.org 
> [mailto:public-webrtc-request@w3.org] On Behalf Of Randell Jesup
> Sent: 24 August 2011 21:13
> To: public-webrtc@w3.org
> Subject: Re: Mapping of media streams to RTP (Re: Query: What 
> does "context" mean in the context (sic) of requirement A15? 
> [ACTION-6])
> 
> On 8/24/2011 11:47 AM, Elwell, John wrote:
> >> RTCP doesn't have a delay if a SR is the first thing sent on
> >> a session,
> >> as recommended in draft-perkins-avt-rapid-rtp-sync-03 
> section 2.1.1 -
> >> this is permitted by RFC 3550 too, it notes.
> > [JRE] OK, so CNAME can be used to map an RTP stream to a 
> given media description in SDP. CNAME alone does not indicate 
> the purpose of an RTP stream - it would still need something 
> else to map it to "game" or "agent", and that is where 
> a=content comes in.
> 
> Don't count on RTCP getting received...  Start of a session 
> might even 
> be the worst place for it.
> 
> -- 
> Randell Jesup
> randell-ietf@jesup.org
> 
> 
> 
Received on Thursday, 25 August 2011 07:51:34 UTC

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