Re: [rtcweb] SDP Offer/Answer draft-jennings-rtcweb-signaling

Cullen Jennings <> Tue, 18 October 2011 18:41 UTC

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From: Cullen Jennings <>
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Date: Tue, 18 Oct 2011 11:41:52 -0700
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To: Ravindran Parthasarathi <>
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Subject: Re: [rtcweb] SDP Offer/Answer draft-jennings-rtcweb-signaling
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So I might have messed up the draft a bit. I'm fine with things can be implemented as dialog statefull, what I want is that it is possible to make a signaling gateway that is only transaction statefull. I'm fine if some signaling gateways are built as dialog statefull.

 (As a side note, some B2BUA are effectively transaction statefull but that is pretty rare )

On Oct 17, 2011, at 15:28 , Ravindran Parthasarathi wrote:

> Cullen/Joanthan,
> I like your proposed idea as it is going in the direction of having
> "standard" signaling protocol for RTCWeb. I'm seeing your proposal as
> SDP offer/answer over websocket and the proposal helps to easy gateway
> development between RTCWeb server and legacy signaling protocols.
> I have fundamental question in the proposal as it proposes RTCWeb server
> as SIP proxy equivalent and in reality, unfortunately most of the SIP
> deployment work is based on B2BUA. The question is whether RTCWeb server
> shall be dialog-state or MUST be transaction-stateful only. 
> Also, session-id in the draft is used to uniquely understand the offerer
> and answerer in the transaction or session. In case it is session, how
> to indicate the termination of the session.

My personal opinion is that to be able to clean up all the state in a clean an easy way, we should add some message to indicate the SDP offer / answer state and related media streams can be discarded.  I'd like to add that to the next version. 

> Thanks
> Partha
>> -----Original Message-----
>> From: [] On
> Behalf
>> Of Cullen Jennings
>> Sent: Saturday, October 15, 2011 8:39 AM
>> To:;
>> Cc: Jonathan Rosenberg
>> Subject: [rtcweb] SDP Offer/Answer draft-jennings-rtcweb-signaling
>> Jonathan and I submitted a new draft on setting up media based on the
>> SDP Offer/Answer model. The ASCII flows are a bit hard to read so until
>> I update them, I recommend reading the PDF version at
>> Clearly the draft is an early stage but we plan to revise it before the
>> deadline for the IETF 82. Love to get input - particularly on if this
>> looks like generally the right direction to go.
>> _______________________________________________
>> rtcweb mailing list