Re: [rtcweb] Use of offer / answer semantics
Emil Ivov <emcho@jitsi.org> Tue, 06 September 2011 15:50 UTC
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Date: Tue, 06 Sep 2011 18:52:06 +0300
From: Emil Ivov <emcho@jitsi.org>
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To: Matthew Kaufman <matthew.kaufman@skype.net>
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Cc: rtcweb@ietf.org
Subject: Re: [rtcweb] Use of offer / answer semantics
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Hey Matthew, На 06.09.11 18:20, Matthew Kaufman написа: > On 9/6/2011 7:46 AM, Cullen Jennings wrote: >> In my roll as an individual contributor, I want to propose some >> text that I think we can get rough consensus on around that helps >> specify which parts of the signaling issues we agree on and which >> we don't. >> >> At the last meeting, my read of the the room was there was a fair >> amount of agreement in the room that offer / answer semantics with >> SDP are what we want to use. I don't think there was was broad >> agreement on if one should use SIP or not, or for that matter >> jingle. If we can nail down this decisions as the direction the WG >> is going, it will really help make progress. What I would like to >> do is propose some following principles in the text below. If we >> have agreement on these, then they would go into the overview >> document and help guide the design of other documents. I want to >> highlight that none of the principles below imply that we would >> need to use SIP in the browsers - the principals would all work >> fine if we there was signaling gateway in the web server that >> converged SIP to whatever proprietary HTML / JS / HTTP that the >> applications wanted to use between the browser and the web server. >> >> >> >> 1) The media negotiations will be done using the same SDP >> offer/answer semantics that are used in SIP. > > I think this would be unfortunate. We have an opportunity here to not > repeat this mistake. I'd be interested in hearing what mistakes you have in mind. > And *if* we go down this road, we need additional language around > things like exposing the capabilities via an API that doesn't start > the offer/answer process itself. (Use case: determine if a browser > has an appropriate camera and encoder before suggesting that they > call the customer service rep for a live chat.) +1 Personally I'd vote for mimicing XMPP's service discovery here. (see XEP-0030 and XEP-0115 on http://xmpp.org/extensions ) I definitely think discovery of capabilities should not be part of the offer/answer negotiation. Emil -- http://jitsi.org
- [rtcweb] Use of offer / answer semantics Cullen Jennings
- Re: [rtcweb] Use of offer / answer semantics Colin Perkins
- Re: [rtcweb] Use of offer / answer semantics Matthew Kaufman
- Re: [rtcweb] Use of offer / answer semantics Emil Ivov
- Re: [rtcweb] Use of offer / answer semantics Emil Ivov
- Re: [rtcweb] Use of offer / answer semantics Colin Perkins
- Re: [rtcweb] Use of offer / answer semantics Emil Ivov
- Re: [rtcweb] Use of offer / answer semantics Cullen Jennings
- Re: [rtcweb] Use of offer / answer semantics Cullen Jennings
- Re: [rtcweb] Use of offer / answer semantics Cullen Jennings
- Re: [rtcweb] Use of offer / answer semantics Harald Alvestrand
- Re: [rtcweb] Use of offer / answer semantics Henry Sinnreich
- Re: [rtcweb] Use of offer / answer semantics Bernard Aboba
- Re: [rtcweb] Use of offer / answer semantics Tim Panton
- Re: [rtcweb] Use of offer / answer semantics Harald Alvestrand
- Re: [rtcweb] Use of offer / answer semantics Olle E. Johansson
- Re: [rtcweb] Use of offer / answer semantics Roman Shpount
- Re: [rtcweb] Use of offer / answer semantics Paul Kyzivat
- Re: [rtcweb] Use of offer / answer semantics Dzonatas Sol
- Re: [rtcweb] Use of offer / answer semantics Paul Kyzivat
- Re: [rtcweb] Use of offer / answer semantics Hadriel Kaplan
- Re: [rtcweb] Use of offer / answer semantics Olle E. Johansson
- [rtcweb] Supporting legacy PSTN interop (was: Use… Hadriel Kaplan
- Re: [rtcweb] Supporting legacy PSTN interop (was:… Ravindran Parthasarathi
- Re: [rtcweb] Use of offer / answer semantics Randell Jesup
- Re: [rtcweb] Use of offer / answer semantics Hadriel Kaplan