Re: [rtcweb] Media forking solution for SIP interoperability (without a media gateway)

Iñaki Baz Castillo <ibc@aliax.net> Mon, 31 October 2011 17:27 UTC

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Date: Mon, 31 Oct 2011 18:27:21 +0100
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From: Iñaki Baz Castillo <ibc@aliax.net>
To: Hadriel Kaplan <HKaplan@acmepacket.com>
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Subject: Re: [rtcweb] Media forking solution for SIP interoperability (without a media gateway)
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2011/10/31 Hadriel Kaplan <HKaplan@acmepacket.com>:
>> SIP media forking can be implemented in JavaScript without mandating
>> special requirements in WebRTC for interoperating with "legacy" SIP
>> (why do we call "legacy" to SIP???). And we just need  tu use existing
>> SIP mechanisms.
>
> Right, as I said before, we don't actually have to implement ROAP forking in the browser, because the JS+Server code can be clever enough to do it, even to SIP.
>
> The question is if we should implement it in the browser anyway, to make things work better for the scenarios where they do go to SIP.
>
> We know that even an interworking-function can "hide" the forking, because they do that right now for SIP-H.323; but we also know that doing so is error-prone and causes media-clipping.
>
> So if it's not too difficult/complicated to implement, handling it natively in the browser is likely to yield the best user experience.  And the nice thing is that if the browsers get it wrong, or the WebApp doesn't want to do it, the JS+Server can still fix it or make it not happen.

I agree. In case it does not add a great complexity at API level it
would be great if we can reuse same local candidates in more than a
single PeerConnection.


>> No signaling gateway is required (of course !!) nor a media gateway
>> (if second bullet in "Assumtions" section above is satisfied).
>>
>> We all are happy (but those who have in mind a market selling
>> WebRTC-SIP gateway boxes and want that the specs satisfy their
>> business model).
>
> I hope you don't think I'm arguing for things for the purpose of selling WebRTC-SIP gateways.

Not at all, of course. You try to make WebRTC design open so any
developer can implement whatever he wants without being constrained to
specific and mandatory in-the-wire protocol or message format.


> I'm trying very hard to list all the things a WebRTC domain must do if it wants to *avoid* gateways.

Yes, it's clear in the draft ;)


> [Not because my company doesn't plan on selling WebRTC-SIP gateways - but because people should use gateways/SBCs when they need to for security/control/etc., but not simply to interoperate.]

Agreed.


-- 
Iñaki Baz Castillo
<ibc@aliax.net>