Re: [rtcweb] Remote recording - RTC-Web client acting as SIPREC session recording client

Igor Faynberg <> Wed, 24 August 2011 16:42 UTC

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Date: Wed, 24 Aug 2011 12:43:48 -0400
From: Igor Faynberg <>
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Subject: Re: [rtcweb] Remote recording - RTC-Web client acting as SIPREC session recording client
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On 8/24/2011 8:04 AM, Harald Alvestrand wrote:
> ...
> I would like to focus on the functionality you think we need for this 
> flexibility - if we really need it, I would like to capture it in an 
> use case; if it's not vitally needed, I would like to leave it for 
> further work.

I agree. A written use case is a must and it is the first thing to do. 
The ball is in my yard.
> I don't know what it would mean to support SUBSCRIBE/NOTIFY without 
> supporting SIP. 

To me, that would mean supporting only REGISTER, SUBSCRIBE/NOTIFY, and 

> I'm not sure I want to have that discussion - it seems to me that some 
> applications will require presence and subscription to presence, but 
> that little of this has to be built into the browser; the Gmail chat 
> function, which indeed exposes presence and subscription, has no 
> browser component at all.

There is a huge SIP-based legacy out there.  For the case where the 
browser is the de-facto OS on an Internet appliance, applications will 
need to be re-written to rely on WebRTC API and rely on RTCWeb 
protocol.  The question is whether SIP client can be efficiently 
implemented without the browser taking care of some critical pieces.  (I 
don't know the answer.)  This is what has been the gist of my intervention.

>> ...
> have you absorbed this?
> "Notification" is not a term that can be used without context - it 
> means very many different things to different people. So one reason 
> why you did not get sufficient discussion might be that we didn't have 
> a shared understanding of what you were asking.

I will need to read this. Thanks for the pointer!