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

Harald Alvestrand <harald@alvestrand.no> Sat, 13 August 2011 20:11 UTC

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Date: Sat, 13 Aug 2011 22:11:40 +0200
From: Harald Alvestrand <harald@alvestrand.no>
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To: Christer Holmberg <christer.holmberg@ericsson.com>
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Subject: Re: [rtcweb] draft-alvestrand-one-rtp-00.txt and intermediaires
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On 08/13/11 00:26, Christer Holmberg wrote:
> Hi Harald,
> When putting the draft together, did you consider intermediaires that 
> do not support the mechanism? Even if the endpoints support it, 
> intermediaries would still see and expect separate streams.
I had not really considered this .... I am not convinced it is a problem.
Brief analysis:

Either they are in the media path or they are not in the media path.

If they are not in the media path, they will not see the difference, and 
will not care.

If they are in the media path.... we have a problem, but that same 
problem applies to any other SDP extension that affects the media, such 
as RTCP multiplexing; if that's successful, that's a hopeful sign that 
they either don't exist or aren't important.

(One special form of "intermediares" are wiretap units - they are in 
fact mentioned in the draft...)