Re: [rtcweb] draft-roach-mmusic-unified-plan-00 expired

Christer Holmberg <christer.holmberg@ericsson.com> Wed, 22 January 2014 15:58 UTC

Return-Path: <christer.holmberg@ericsson.com>
X-Original-To: rtcweb@ietfa.amsl.com
Delivered-To: rtcweb@ietfa.amsl.com
Received: from localhost (ietfa.amsl.com [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id E511E1A0445 for <rtcweb@ietfa.amsl.com>; Wed, 22 Jan 2014 07:58:41 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.569
X-Spam-Level:
X-Spam-Status: No, score=-2.569 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, HELO_EQ_SE=0.35, HTML_FONT_FACE_BAD=0.981, HTML_MESSAGE=0.001, MIME_8BIT_HEADER=0.3, RCVD_IN_DNSWL_MED=-2.3, SPF_PASS=-0.001] autolearn=ham
Received: from mail.ietf.org ([4.31.198.44]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Ns-N6q1b-upY for <rtcweb@ietfa.amsl.com>; Wed, 22 Jan 2014 07:58:39 -0800 (PST)
Received: from mailgw1.ericsson.se (mailgw1.ericsson.se [193.180.251.45]) by ietfa.amsl.com (Postfix) with ESMTP id 32E331A043B for <rtcweb@ietf.org>; Wed, 22 Jan 2014 07:58:35 -0800 (PST)
X-AuditID: c1b4fb2d-b7f5d8e000002a7b-af-52dfeaa9b0a9
Received: from ESESSHC020.ericsson.se (Unknown_Domain [153.88.253.124]) by mailgw1.ericsson.se (Symantec Mail Security) with SMTP id 46.BC.10875.9AAEFD25; Wed, 22 Jan 2014 16:58:34 +0100 (CET)
Received: from ESESSMB209.ericsson.se ([169.254.9.114]) by ESESSHC020.ericsson.se ([153.88.183.78]) with mapi id 14.02.0387.000; Wed, 22 Jan 2014 16:58:33 +0100
From: Christer Holmberg <christer.holmberg@ericsson.com>
To: Iñaki Baz Castillo <ibc@aliax.net>, Paul Kyzivat <pkyzivat@alum.mit.edu>
Thread-Topic: [rtcweb] draft-roach-mmusic-unified-plan-00 expired
Thread-Index: AQHPF38oIO7L40kANU2m8H3Z3gS+PpqQ5ptg
Date: Wed, 22 Jan 2014 15:58:33 +0000
Message-ID: <7594FB04B1934943A5C02806D1A2204B1D115528@ESESSMB209.ericsson.se>
References: <CALiegfkJe1QfMcPoDg4+71oujHUzJy86_pnLXDO9C=g_v8_4Lg@mail.gmail.com> <7594FB04B1934943A5C02806D1A2204B1D107730@ESESSMB209.ericsson.se> <CALiegfkhs5JeVj-2YL2QJgwMgB1cP77aUZEWdoywQCpQd_O6Ag@mail.gmail.com> <7594FB04B1934943A5C02806D1A2204B1D10819E@ESESSMB209.ericsson.se> <CALiegfmyOayaz41FM+3xF733srs8MUKGMumW7nAfT53EnfEaWw@mail.gmail.com> <52DD7889.8030209@alum.mit.edu>, <CALiegfn1CwsOmN7TdFvBG-5590q9dmyhyRJK3H6u15Ux6H=LNQ@mail.gmail.com>
In-Reply-To: <CALiegfn1CwsOmN7TdFvBG-5590q9dmyhyRJK3H6u15Ux6H=LNQ@mail.gmail.com>
Accept-Language: en-US
Content-Language: en-US
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
Content-Type: multipart/alternative; boundary="_000_7594FB04B1934943A5C02806D1A2204B1D115528ESESSMB209erics_"
MIME-Version: 1.0
X-Brightmail-Tracker: H4sIAAAAAAAAA+NgFnrILMWRmVeSWpSXmKPExsUyM+Jvje6qV/eDDF5/5LOYvs/GYsWGA6wW a/+1szswe5xreM/u8ff9ByaPJUt+MgUwR3HZpKTmZJalFunbJXBlTHnZwl7wybvizqRP7A2M Tzy7GDk5JARMJDZef8cCYYtJXLi3nq2LkYtDSOAQo8SXD9NYIJwljBJNSz8ydTFycLAJWEh0 /9MGaRARSJG4/vs0M4jNLKAucWfxOXYQW1jAQeLKrdNMEDWOEq9bL7ND2EYSa58+AlvGIqAq 8av/GCuIzSvgK3HmxX0miF1nmSWu/mwGS3AKBEp8nzOfEcRmBLru+6k1TBDLxCVuPZnPBHG1 gMSSPeeZIWxRiZeP/7FC1ORL9F3cxAaxQFDi5MwnLBMYRWYhaZ+FpGwWkrJZQG8yC2hKrN+l D1GiKDGl+yE7hK0h0TpnLjuy+AJG9lWM7LmJmTnp5YabGIHRdHDLb90djKfOiRxilOZgURLn /fDWOUhIID2xJDU7NbUgtSi+qDQntfgQIxMHp1QDo0GVXKyuUctBV7W78rcaj8SzHuHi71yS ql6w/Nixtdxh2s92GNz3cClI3J6mnXtnVpO2+Zm7igtf8foeFbULv3R3x8T21YGaRnq1vyd8 K3R3kg8QLZs94Yn0bEX+X8zh8QECHbcEFvBmeZRnXFc2yrq9d9IUtRcMv7LKFML9rKaW8nQm PjimxFKckWioxVxUnAgAnV+xlHQCAAA=
Cc: "rtcweb@ietf.org" <rtcweb@ietf.org>
Subject: Re: [rtcweb] draft-roach-mmusic-unified-plan-00 expired
X-BeenThere: rtcweb@ietf.org
X-Mailman-Version: 2.1.15
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: Wed, 22 Jan 2014 15:58:42 -0000

Hi,

I thought the idea of the UP was that each m- line was going to represent a unidirectional stream, which would make it easier to negotiate a different number of streams per direction.

But, maybe I remember wrong….

Regards,

Christer

Sent from Windows Mail

From: Iñaki Baz Castillo<mailto:ibc@aliax.net>
Sent: ‎Wednesday‎, ‎January‎ ‎22‎, ‎2014 ‎4‎:‎35‎ ‎PM
To: Paul Kyzivat<mailto:pkyzivat@alum.mit.edu>
Cc: rtcweb@ietf.org<mailto:rtcweb@ietf.org>

2014/1/20 Paul Kyzivat <pkyzivat@alum.mit.edu>:
> What is it that troubles you about this.
>
> I guess from prior comment that you want to add more m-lines in the answer?
>
> But O/A is a negotiation/handshake. If you include extra m-lines in the
> answer then there is no completion to the negotiation of those.

Having two endpoints establshing a media session, the only they need is:

- To decide a transport or transports for sending media one to each other.
- To tell one to each other what it is sending.

SDP is good (enough) in classic and simple communications in which
both endpoints send and receive something similar (i.e. one single
audio track in both directions).

But nowadays we want that endpoint-A can send just one audio track and
one video track and receive 8 audio tracks and 8 video tracks from
endpoint-B. If endpoint-A makes the SDP offer, it "should" include 16
m lines:

- 1 audio line for sending its single audio track and receive *one* of
the remote tracks (a=sendrecv).
- 7 audio tracks just for receiving the rest of the remote audio
tracks (a=recvonly).
- Same for video.

This is completely unnecessary if we skip the SDP tradition. There is
no need at all for endpoint-A to tell endpoint-B "you can send me up
to 8 audio tracks since I have added 8 m audio lines in my SDP offer,
otherwise you can only send me a single audio track, but you can send
me later a re-offer".

This is something that ORTC "fixes".

Regards.



--
Iñaki Baz Castillo
<ibc@aliax.net>
_______________________________________________
rtcweb mailing list
rtcweb@ietf.org
https://www.ietf.org/mailman/listinfo/rtcweb