Re: Some ideas on SVC support in WebRTC 1.0 (Take 2)

Inaki said:

"Please, don't forget RTX/FLEXFEC stuff in simulcast. If RID is used, RRID must be used. If just SSRC is used then ssrc-group is needed. Etc etc."

[BA]  JSEP does not mention RRID, nor do any of the examples include the repaired-rtp-stream-id in the SDP.  However, RRID is mentioned in draft-ietf-mmusic-sdp-simulcast and SDP examples such as Figure 7 do include it.

With respect to the object model, there was a discussion of RRID two years ago:
https://github.com/w3c/ortc/issues/406

Conclusion seemed to be that it was not necessary, but perhaps the conclusion was too hasty.
[https://avatars3.githubusercontent.com/u/808811?s=400&v=4]<https://github.com/w3c/ortc/issues/406>

RRID support · Issue #406 · w3c/ortc · GitHub<https://github.com/w3c/ortc/issues/406>
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________________________________
From: Iñaki Baz Castillo <ibc@aliax.net>
Sent: Thursday, July 12, 2018 2:03 PM
To: Bernard Aboba
Cc: Harald Alvestrand; WebRTC WG
Subject: Re: Some ideas on SVC support in WebRTC 1.0 (Take 2)

Please, don't forget RTX/FLEXFEC stuff in simulcast. If RID is used, RRID must be used. If just SSRC is used then ssrc-group is needed. Etc etc.

Too many ways to express the same does not usually end well.

El jue., 12 jul. 2018 22:59, Bernard Aboba <Bernard.Aboba@microsoft.com<mailto:Bernard.Aboba@microsoft.com>> escribió:

Harald said:

“It seems that -jsep took away the requirement to generate a=ssrc in version -17. Should we attempt to add it back, or should we just depend on the good graces of the implementors?”



[BA] I don’t think we need to change JSEP.  Implementers appear to understand the backward compatibility issues. If SFUs eventually support MID and RID header extensions, then “a=ssrc” line support will be less necessary, and then having a mandate in the specification would become a “ball and chain”.