Re: [ppsp] re-charter issue discussion(cont'):transport mechanism

Arno Bakker <arno@cs.vu.nl> Tue, 10 April 2012 09:49 UTC

Return-Path: <a.bakker@vu.nl>
X-Original-To: ppsp@ietfa.amsl.com
Delivered-To: ppsp@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id DF8B221F882D for <ppsp@ietfa.amsl.com>; Tue, 10 Apr 2012 02:49:56 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.104
X-Spam-Level:
X-Spam-Status: No, score=-1.104 tagged_above=-999 required=5 tests=[AWL=-0.800, BAYES_00=-2.599, HELO_EQ_NL=0.55, HOST_EQ_NL=1.545, J_CHICKENPOX_31=0.6, J_CHICKENPOX_63=0.6, RCVD_IN_DNSWL_LOW=-1]
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 gYg+8Zr1Dlgw for <ppsp@ietfa.amsl.com>; Tue, 10 Apr 2012 02:49:56 -0700 (PDT)
Received: from mailin.vu.nl (mailin.vu.nl [130.37.164.18]) by ietfa.amsl.com (Postfix) with ESMTP id 0FEBD21F8826 for <ppsp@ietf.org>; Tue, 10 Apr 2012 02:49:55 -0700 (PDT)
Received: from PEXHB011A.vu.local (130.37.236.64) by mailin.vu.nl (130.37.164.18) with Microsoft SMTP Server (TLS) id 14.2.283.3; Tue, 10 Apr 2012 11:49:54 +0200
Received: from [130.37.193.73] (130.37.238.20) by mails.vu.nl (130.37.236.64) with Microsoft SMTP Server (TLS) id 14.2.283.3; Tue, 10 Apr 2012 11:49:53 +0200
Message-ID: <4F84025C.3040206@cs.vu.nl>
Date: Tue, 10 Apr 2012 11:50:20 +0200
From: Arno Bakker <arno@cs.vu.nl>
User-Agent: Mozilla/5.0 (Windows NT 6.1; rv:11.0) Gecko/20120312 Thunderbird/11.0
MIME-Version: 1.0
To: ppsp <ppsp@ietf.org>
References: <2012033016511639412036@chinamobile.com>
In-Reply-To: <2012033016511639412036@chinamobile.com>
Content-Type: text/plain; charset="ISO-8859-1"; format="flowed"
Content-Transfer-Encoding: 7bit
X-Originating-IP: [130.37.238.20]
Subject: Re: [ppsp] re-charter issue discussion(cont'):transport mechanism
X-BeenThere: ppsp@ietf.org
X-Mailman-Version: 2.1.12
Precedence: list
Reply-To: arno@cs.vu.nl
List-Id: discussing to draw up peer to peer streaming protocol <ppsp.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/ppsp>, <mailto:ppsp-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/ppsp>
List-Post: <mailto:ppsp@ietf.org>
List-Help: <mailto:ppsp-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/ppsp>, <mailto:ppsp-request@ietf.org?subject=subscribe>
X-List-Received-Date: Tue, 10 Apr 2012 09:49:57 -0000

On 30/03/2012 10:53, zhangyunfei wrote:
> Hi all,
> To continue the re-charter discussion in PPSP WG meeting, I would like
> to discuss more on the transport mechanism issue.
> I happen to know in RTCWeb, the transport protocol between two peer
> browsers seems to been decided: For media part, srtp/rtp over UDP(I am
> not quite sure of if it is accurate). For data transmit, Datagrams over
> SCTP over DTLS over UDP.
> My question is: If this related to PPSP transport mechanism? Or totally
> two different things?Any different requirements? Just to provide such
> info to incur discussion.

Hi all

to keep the re-charter discussion brief could we perhaps split the
discussion into (1) where media transport aspects should be discussed
and (2) what the transport actually is.

For (1), I'd like to keep it inside the peer protocol spec, as mentioned 
before.

For (2): The RTCWEB work is definitely relevant, so thanks for keeping 
us up-to-date, Yunfei. There are of course differences, notably PPSP is 
also about time-shifted streaming, i.e. video-on-demand. This means 
real-time is not always relevant and we also need to think about 
post-view seeding. The latter makes LEDBAT support important.
Furthermore, sender authentication and privacy may be less important for 
us than in the RTCWEB teleconferencing scenarios.
Also PPSP is more about one-to-many than RTCWEB, although they may be
looking at that too.

I think we should definitely advocate our work in RTCWEB, but in Canada 
they weren't ready for P2P scenarios yet, and I haven't followed their 
progress since.

CU,
      Arno