[AVTCORE] Query: Reporting SSRC when you send no streams?

Harald Alvestrand <harald@alvestrand.no> Mon, 01 June 2015 08:59 UTC

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Date: Mon, 01 Jun 2015 10:59:39 +0200
From: Harald Alvestrand <harald@alvestrand.no>
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Subject: [AVTCORE] Query: Reporting SSRC when you send no streams?
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This came up in a WebRTC-related context:

If you send no streams, what SSRC should you be using in receiver reports?

If you start sending streams, should your reporting SSRC(s) change?

If you stop sending streams, what should happen? Keep reporting from the 
stream(s) that are gone, or switch to a new (old?) non-sending SSRC?

I'm looking at draft-ietf-avtcore-rtp-multi-stream (and -optimization), 
and they seem to offer plenty of advice for the case where there is more 
than one stream (report on them all in -multi-stream, add them to a 
group in -optimization), but not specifically for the 0->1, 1->0 
transitions.

Of course, I may have overlooked something...

Harald