Re: [rtcweb] Reasons (not?) to multiplex audio with video

Harald Alvestrand <harald@alvestrand.no> Tue, 26 July 2011 21:46 UTC

Return-Path: <harald@alvestrand.no>
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 888FB21F8793 for <rtcweb@ietfa.amsl.com>; Tue, 26 Jul 2011 14:46:01 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -102.599
X-Spam-Level:
X-Spam-Status: No, score=-102.599 tagged_above=-999 required=5 tests=[AWL=0.000, BAYES_00=-2.599, USER_IN_WHITELIST=-100]
Received: from mail.ietf.org ([64.170.98.30]) by localhost (ietfa.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id Jsbatm6Hgcnw for <rtcweb@ietfa.amsl.com>; Tue, 26 Jul 2011 14:46:01 -0700 (PDT)
Received: from eikenes.alvestrand.no (eikenes.alvestrand.no [158.38.152.233]) by ietfa.amsl.com (Postfix) with ESMTP id EFA4E21F8797 for <rtcweb@ietf.org>; Tue, 26 Jul 2011 14:46:00 -0700 (PDT)
Received: from localhost (localhost [127.0.0.1]) by eikenes.alvestrand.no (Postfix) with ESMTP id 415F839E091 for <rtcweb@ietf.org>; Tue, 26 Jul 2011 23:44:52 +0200 (CEST)
X-Virus-Scanned: Debian amavisd-new at eikenes.alvestrand.no
Received: from eikenes.alvestrand.no ([127.0.0.1]) by localhost (eikenes.alvestrand.no [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 4kiPj4mq3I4T for <rtcweb@ietf.org>; Tue, 26 Jul 2011 23:44:51 +0200 (CEST)
Received: from [130.129.22.244] (dhcp-16f4.meeting.ietf.org [130.129.22.244]) by eikenes.alvestrand.no (Postfix) with ESMTPS id BD72839E082 for <rtcweb@ietf.org>; Tue, 26 Jul 2011 23:44:50 +0200 (CEST)
Message-ID: <4E2F359C.8060100@alvestrand.no>
Date: Tue, 26 Jul 2011 17:46:04 -0400
From: Harald Alvestrand <harald@alvestrand.no>
User-Agent: Mozilla/5.0 (X11; U; Linux x86_64; en-US; rv:1.9.2.18) Gecko/20110617 Thunderbird/3.1.11
MIME-Version: 1.0
To: rtcweb@ietf.org
References: <4E123C54.10405@jdrosen.net> <8785C0A3-31E5-44D7-8557-3BEEE4F95E3D@skype.net> <4E2D5C5D.6060402@alvestrand.no> <f06240801ca54cb571321@[66.80.62.44]>
In-Reply-To: <f06240801ca54cb571321@[66.80.62.44]>
Content-Type: text/plain; charset="ISO-8859-1"; format="flowed"
Content-Transfer-Encoding: 7bit
Subject: Re: [rtcweb] Reasons (not?) to multiplex audio with video
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: Tue, 26 Jul 2011 21:46:01 -0000

On 07/26/11 16:55, Ross Finlayson wrote:
>
> 3/ Google Plus "Hangouts".  Similar question to 1/.
Google+ Hangouts uses SRTP, with one port for video and one port for 
audio. Many audio and video channels (multiplexed by SSRC) in the 
server->client direction.

We multiplex RTCP onto the RTP port as specified in the relevant RFC.

                       Harald