Re: [MMUSIC] FW: [rtcweb] How to signal RTX SSRCs with simulcast

Adam Roach <adam@nostrum.com> Wed, 26 July 2017 17:01 UTC

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To: Bernard Aboba <bernard.aboba@gmail.com>
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From: Adam Roach <adam@nostrum.com>
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Date: Wed, 26 Jul 2017 12:01:28 -0500
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Subject: Re: [MMUSIC] FW: [rtcweb] How to signal RTX SSRCs with simulcast
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On 7/26/17 11:34, Bernard Aboba wrote:
> Currently the WebRTC API only exposes RIDs used for media streams, not 
> for redundancy streams and JSEP currently doesn't indicate whether it 
> is permitted for redundancy streams to have their own RIDs.

Not all SDP attributes are exposed or controllable through the WebRTC 
API, mostly because there's an SDP world outside WebRTC. For example, 
CLUE adds new group types to SDP, but we don't fret about surfacing them 
in web browsers. I think we can safely say that your typical WebRTC 
implementation will neither produce nor consume these; they'll just be 
safely ignored.

Well, right up until the moment that you find a use case that requires 
them, at least.

/a