Re: [rtcweb] Making progress on the signaling discussion (NB: Action items enclosed!)

Randell Jesup <randell-ietf@jesup.org> Thu, 13 October 2011 04:33 UTC

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Date: Thu, 13 Oct 2011 00:29:28 -0400
From: Randell Jesup <randell-ietf@jesup.org>
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Subject: Re: [rtcweb] Making progress on the signaling discussion (NB: Action items enclosed!)
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On 10/12/2011 6:49 PM, Roman Shpount wrote:
>
>
> On Wed, Oct 12, 2011 at 6:21 PM, Randell Jesup <randell-ietf@jesup.org
> <mailto:randell-ietf@jesup.org>> wrote:
>
>     See my much earlier discussion of Forking support by modifying
>     Harald's OFFER/ANSWER messages to include ACCEPT, which also helps
>     solve the answer-time clipping issues.
>
>     (I'll try to dig it out of the archives and repost a link.)
>
>
> I do remember your proposal, and it does address the situation where
> JavaScript would need to update the remote target. I am not sure it
> covers the case where multiple streams need to be created based on
> several answers to the same offer (flow that corresponds to multiple 200
> OK responses to a single INVITE).

It did cover that case - it was up to the app what to do when the first 
ACCEPT was processed.  I didn't go into the JS-level mechanisms used.

> I don't think it would be very
> difficult to implement disambiguation of multiple remote media sources
> based on remote IP and allow JavaScript to manage each stream
> separately.

Do not assume that remote IP == source - this is easily provably false, 
though if you used remote IP+port AND local IP+port I think it would be 
ok.  However, for each remote connection we should have a DTLS 
connection instance, so that's probably simplest.

> I would suggest some sort of CLONE API, taking the remote
> description and creating a new stream, for this purpose.

Quite possibly this is really a W3C area...  though they're all 
interrelated.

-- 
Randell Jesup
randell-ietf@jesup.org