Re: [rtcweb] consent freshness [was RE: STUN for keep-alive]

Randell Jesup <randell-ietf@jesup.org> Thu, 22 September 2011 16:51 UTC

Return-Path: <randell-ietf@jesup.org>
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 2739D21F84D2 for <rtcweb@ietfa.amsl.com>; Thu, 22 Sep 2011 09:51:58 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.611
X-Spam-Level:
X-Spam-Status: No, score=-2.611 tagged_above=-999 required=5 tests=[AWL=-0.012, BAYES_00=-2.599]
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 7dKnlTbOVFLf for <rtcweb@ietfa.amsl.com>; Thu, 22 Sep 2011 09:51:57 -0700 (PDT)
Received: from r2-chicago.webserversystems.com (r2-chicago.webserversystems.com [173.236.101.58]) by ietfa.amsl.com (Postfix) with ESMTP id 9545621F84D9 for <rtcweb@ietf.org>; Thu, 22 Sep 2011 09:51:57 -0700 (PDT)
Received: from pool-173-49-141-165.phlapa.fios.verizon.net ([173.49.141.165] helo=[192.168.1.12]) by r2-chicago.webserversystems.com with esmtpsa (TLSv1:AES256-SHA:256) (Exim 4.69) (envelope-from <randell-ietf@jesup.org>) id 1R6mXd-0003j7-E9 for rtcweb@ietf.org; Thu, 22 Sep 2011 11:54:29 -0500
Message-ID: <4E7B6774.7040601@jesup.org>
Date: Thu, 22 Sep 2011 12:51:00 -0400
From: Randell Jesup <randell-ietf@jesup.org>
User-Agent: Mozilla/5.0 (Windows NT 5.1; rv:6.0.1) Gecko/20110830 Thunderbird/6.0.1
MIME-Version: 1.0
To: rtcweb@ietf.org
References: <7F2072F1E0DE894DA4B517B93C6A05852233EDB21D@ESESSCMS0356.eemea.ericsson.se><1D062974A4845E4D8A343C653804920206648D0F@XMB-BGL-414.cisco.com><7F2072F1E0DE894DA4B517B93C6A05852233EDB3E5@ESESSCMS0356.eemea.ericsson.se><4E70D2E6.1000809@alvestrand.no><CABcZeBORi5NLSsztnMfkwL43p9oKG9mi6e1WWOaiafAO_DpTVg@mail.gmail.com><7F2072F1E0DE894DA4B517B93C6A05852233D45FA3@ESESSCMS0356.eemea.ericsson.se><CABcZeBO9hUSYZhLrcfbaK9HLGXq-q1EvqWOy6-gAN5xom6Z2-A@mail.gmail.com><092401cc749b$8fd64940$af82dbc0$@com><CABcZeBPgRD6kb2gg=m9NckSa1wrzwzJS6527nYqFG34b0cjfgQ@mail.gmail.com><4E765E4A.3050801@alvestrand.no><0ced01cc76de$28731630$79594290$@com> <4E77613B.4020805@ericsson.com> <1D062974A4845E4D8A343C6538049202066497EF@XMB-BGL-414.cisco.com> <4E784C38.2010909@ericsson.com> <1D062974A4845E4D8A343C65380492020672C04A@XMB-BGL-414.cisco.com> <4E7B2C04.401 0204@eri csson.com> <1D062974A4845E4D8A343C65380492020672C08F@XMB-BGL-414.cisco.com> <4E7B4F91.8090409@jesup.org> <4E7B5A2F.8020102@ericss on.com>
In-Reply-To: <4E7B5A2F.8020102@ericsson.com>
Content-Type: text/plain; charset="ISO-8859-1"; format="flowed"
Content-Transfer-Encoding: 7bit
X-AntiAbuse: This header was added to track abuse, please include it with any abuse report
X-AntiAbuse: Primary Hostname - r2-chicago.webserversystems.com
X-AntiAbuse: Original Domain - ietf.org
X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12]
X-AntiAbuse: Sender Address Domain - jesup.org
X-Source:
X-Source-Args:
X-Source-Dir:
Subject: Re: [rtcweb] consent freshness [was RE: STUN for keep-alive]
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: Thu, 22 Sep 2011 16:51:58 -0000

On 9/22/2011 11:54 AM, Magnus Westerlund wrote:
> On 2011-09-22 17:09, Randell Jesup wrote:
>> There certainly may be use-cases where media in one (or both)
>> directions are inactive or DTX-muted for considerable periods of time
>> - remember, many of the use-cases (and unknown interesting future
>> uses) aren't "phone calls".
>>
>> In particular, I have some interesting use-cases bubbling in the back
>> of my brain where the data channel remains open at low/no activity
>> and the media channels are inactive or non-existant for long periods,
>> or where data traffic predominates and media are often inactive.
> Yes, I definitely believe you. Which only points that we will need to
> consider issues like how much background traffic that occurs just from
> having the PeerConnection up and being ready for sending media. Maybe
> mandate maximum levels when in practice inactive.
>
> It also has implication I think on the continued media consent. As the
> point raised Muthu is that when none sends media, there is in fact zero
> entropy in the RTCP RR compound packets. Thus RTCP can't be used for that.
I wonder: could we create a default reliable data channel in all
PeerConnections that's used (solely?) for a heartbeat/"consent freshness"?
In that case, we get to define the heartbeat and can mandate enough entropy.
(Receiving data on reliable SCTP (or TCP) over DTLS might be enough right there.)

-- 
Randell Jesup
randell-ietf@jesup.org