Re: [rtcweb] Non-media data service consensus and requirements

Jonathan Rosenberg <jdrosen@jdrosen.net> Tue, 28 June 2011 19:46 UTC

Return-Path: <jdrosen@jdrosen.net>
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 24C1A11E81A7 for <rtcweb@ietfa.amsl.com>; Tue, 28 Jun 2011 12:46:05 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -102.265
X-Spam-Level:
X-Spam-Status: No, score=-102.265 tagged_above=-999 required=5 tests=[BAYES_00=-2.599, IP_NOT_FRIENDLY=0.334, 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 RXE1hi2p2lIp for <rtcweb@ietfa.amsl.com>; Tue, 28 Jun 2011 12:46:04 -0700 (PDT)
Received: from ecbiz71.inmotionhosting.com (ecbiz71.inmotionhosting.com [69.174.48.15]) by ietfa.amsl.com (Postfix) with ESMTP id 27C8411E818F for <rtcweb@ietf.org>; Tue, 28 Jun 2011 12:46:04 -0700 (PDT)
Received: from pool-173-63-59-84.nwrknj.fios.verizon.net ([173.63.59.84] helo=[192.168.1.14]) by ecbiz71.inmotionhosting.com with esmtpsa (TLSv1:AES256-SHA:256) (Exim 4.69) (envelope-from <jdrosen@jdrosen.net>) id 1QbeEU-0000bJ-Sy for rtcweb@ietf.org; Tue, 28 Jun 2011 15:46:02 -0400
Message-ID: <4E0A2F70.9040305@jdrosen.net>
Date: Tue, 28 Jun 2011 15:45:52 -0400
From: Jonathan Rosenberg <jdrosen@jdrosen.net>
User-Agent: Mozilla/5.0 (Windows; U; Windows NT 6.0; en-US; rv:1.9.2.18) Gecko/20110616 Thunderbird/3.1.11
MIME-Version: 1.0
To: rtcweb@ietf.org
References: <4E0832FE.7010401@ericsson.com>
In-Reply-To: <4E0832FE.7010401@ericsson.com>
Content-Type: text/plain; charset="ISO-8859-1"; format="flowed"
Content-Transfer-Encoding: 8bit
X-AntiAbuse: This header was added to track abuse, please include it with any abuse report
X-AntiAbuse: Primary Hostname - ecbiz71.inmotionhosting.com
X-AntiAbuse: Original Domain - ietf.org
X-AntiAbuse: Originator/Caller UID/GID - [47 12] / [47 12]
X-AntiAbuse: Sender Address Domain - jdrosen.net
Subject: Re: [rtcweb] Non-media data service consensus and requirements
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, 28 Jun 2011 19:46:05 -0000

Here are some thoughts on additional use cases:

* information on congestion and receiver side environment for purposes 
of improved sender rate adaptation

* active speaker indications

* real-time text (along the lines of 
http://datatracker.ietf.org/doc/rfc5194/)

* video controls - application driven intra-frame requests, for example

* floor control requests/grants


All of these share the common property of being latency sensitive, and 
thus more appropraite for p2p vs. server mediated. The other driver for 
p2p data transport is cost reduction, to avoid the need for server 
mediation for transfer of data. File transfer is the main example of this.

I view the latency-sensitive use cases as a higher priority for us and a 
better match to the work we're doing here.

Thanks,
Jonathan R.

On 6/27/2011 3:36 AM, Magnus Westerlund wrote:
> WG,
>
> At the interim it was planned to have a bit discussion on the datagram
> service for RTCWEB. The first question to try to resolve if there
> is consensus for including some form of non real-time media (i.e. not
> audio, video) service between peers. This is a bit tangled with the
> actual requirements and use cases. But there was views both for it and
> against it on the mailing list. So lets continue and try to come to a
> conclusion on this discussion.
>
> The use cases mentioned on the mailing list are:
>
> - Dynamic meta data for Conference and other real-time services
>
> - Gaming data with low latency requirements
>
> Does anyone like to add additional use cases?
>
> Based on my personal understanding this points to primarily have the
> RTCWEB provide a unreliable datagram service. This clearly needs
> additional requirements to be secure and safe to deploy, but more about
> this below. I still like to ask the WG here a question.
>
> Are you supporting the inclusion of a unreliable datagram service
> directly between peers? Please provide your view and any additional
> statements of motivation that you desire to provide.
>
> Secondly, there is a question if there needs to have something that
> provides reliable message (of arbitrary size) or byte stream oriented
> data transport between the peers. I personally foresee that people will
> build JS libraries for this on top of a unreliable datagram service. If
> you desire reliable data service as part of the standardized solution
> please provide motivation and use case and requirements.
>
> I also want to take a stab on what I personally see as the requirements
> that exist on unreliable datagram service in the context of RTCWEB.
>
> - Unreliable data transmission
> - Datagram oriented
>     * Size limited by MTU
>       - Path MTU discovery needed
>     * Fragmentation by the application
> - Low latency, i.e. Peer to Peer preferable
> - Congestion Controlled, to be
>     * Network friendly
>     * Not become a Denial of Service tool
> - Security
>    * Confidentiality
>    * Integrity Protected
>    * Source Authenticated (at least bound to the signalling peer)
>    * Ensure consent to receive data
>
> Please debate the above. This is an attempt to ensure that we can
> establish WG consensus on both data service and any requirements.
>
> cheers
>
> Magnus Westerlund
>
> ----------------------------------------------------------------------
> Multimedia Technologies, Ericsson Research EAB/TVM
> ----------------------------------------------------------------------
> Ericsson AB                | Phone  +46 10 7148287
> Färögatan 6                | Mobile +46 73 0949079
> SE-164 80 Stockholm, Sweden| mailto: magnus.westerlund@ericsson.com
> ----------------------------------------------------------------------
>
> _______________________________________________
> rtcweb mailing list
> rtcweb@ietf.org
> https://www.ietf.org/mailman/listinfo/rtcweb

-- 
Jonathan D. Rosenberg, Ph.D.                   SkypeID: jdrosen
Skype Chief Technology Strategist
jdrosen@skype.net                              http://www.skype.com
jdrosen@jdrosen.net                            http://www.jdrosen.net