Re: [rtcweb] No Plan

Enrico Marocco <enrico.marocco@telecomitalia.it> Thu, 30 May 2013 15:53 UTC

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Date: Thu, 30 May 2013 17:53:32 +0200
From: Enrico Marocco <enrico.marocco@telecomitalia.it>
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Subject: Re: [rtcweb] No Plan
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On 5/30/13 5:14 PM, Paul Kyzivat wrote:
>> 1. sender gets the additional local tracks
>>
>> 2. sender tells the receiver on the app-specific signalling channel
>>     (assuming a plain-english-over-something one): "I can also send you
>>     video and audio of a webcam I've just installed in the girls locker
>>     room. They'll have SSRC xxx and yyy" (xxx and yyy retrieved through
>>     JS API -- kind of what exists in Chrome today for stats)
>>
>> 3. receiver responds "Shoot!"
> 
> What does the receiver say if it can use the media, but cannot receive 
> it over the *existing* audio and video m-lines where it is receiving 
> other media already?

I may have misinterpreted the draft, but it seems to me the whole point
here is about having WebRTC endpoints support multiple SSRCs on the same
m-line. If that's the case, an endpoint not supporting that would
qualify as "legacy". It would be behind a gateway anyway, and the
gateway function would be in the best position to translate both SDP and
media in a way it can digest.

Enrico