Re: [rtcweb] A problem with both A and B

Bernard Aboba <bernard_aboba@hotmail.com> Fri, 17 May 2013 20:21 UTC

Return-Path: <bernard_aboba@hotmail.com>
X-Original-To: rtcweb@ietfa.amsl.com
Delivered-To: rtcweb@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 68B5321F95E9 for <rtcweb@ietfa.amsl.com>; Fri, 17 May 2013 13:21:56 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -102.426
X-Spam-Level:
X-Spam-Status: No, score=-102.426 tagged_above=-999 required=5 tests=[AWL=0.173, BAYES_00=-2.599, USER_IN_WHITELIST=-100]
Received: from mail.ietf.org ([12.22.58.30]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id azq4yycIvXdE for <rtcweb@ietfa.amsl.com>; Fri, 17 May 2013 13:21:51 -0700 (PDT)
Received: from blu0-omc3-s33.blu0.hotmail.com (blu0-omc3-s33.blu0.hotmail.com [65.55.116.108]) by ietfa.amsl.com (Postfix) with ESMTP id 5FAF121F9488 for <rtcweb@ietf.org>; Fri, 17 May 2013 13:21:51 -0700 (PDT)
Received: from BLU403-EAS403 ([65.55.116.74]) by blu0-omc3-s33.blu0.hotmail.com with Microsoft SMTPSVC(6.0.3790.4675); Fri, 17 May 2013 13:21:50 -0700
X-EIP: [5WDRjKeICn4Q7hIcoq/FEI/SIRRv7anu]
X-Originating-Email: [bernard_aboba@hotmail.com]
Message-ID: <BLU403-EAS40305B2D015B786CC67EB9293AC0@phx.gbl>
Date: Fri, 17 May 2013 13:21:47 -0700
From: Bernard Aboba <bernard_aboba@hotmail.com>
To: "Dale R. Worley" <worley@ariadne.com>
MIME-Version: 1.0
Content-Transfer-Encoding: quoted-printable
Content-Type: text/plain; charset="utf-8"
X-OriginalArrivalTime: 17 May 2013 20:21:50.0941 (UTC) FILETIME=[2A13D8D0:01CE533C]
Cc: rtcweb@ietf.org
Subject: Re: [rtcweb] A problem with both A and B
X-BeenThere: rtcweb@ietf.org
X-Mailman-Version: 2.1.12
Precedence: list
List-Id: Real-Time Communication in WEB-browsers working group list <rtcweb.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/rtcweb>, <mailto:rtcweb-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/rtcweb>
List-Post: <mailto:rtcweb@ietf.org>
List-Help: <mailto:rtcweb-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/rtcweb>, <mailto:rtcweb-request@ietf.org?subject=subscribe>
X-List-Received-Date: Fri, 17 May 2013 20:21:56 -0000

It is important. In fact, I would argue it is critical for congestion control (e.g. removal of simulcast or layered streams by the sender should not require an O/A exchange).

"Dale R. Worley" <worley@ariadne.com> wrote:

> From: Emil Ivov <emcho@jitsi.org>
>
> Both plan A and B currently describe semantics that would require O/A
> exchanges every time a source is added or removed from a session.
> [...]
> Does any of this make any sense?

My understanding (and I'm not tracking everything carefully) is that
this is a bad situation.  I've been accumulating desiderata, and one
that has been on the list for a long time is:

   DES F11  It must be possible to add and remove one way video flows
      within the bundle without requiring an additional offer/answer
      cycle.

Do people think that this is not important?

Dale
_______________________________________________
rtcweb mailing list
rtcweb@ietf.org
https://www.ietf.org/mailman/listinfo/rtcweb