Re: [rtcweb] Isolating data channels (Re: Asking TLS for help with media isolation)

Michael Tuexen <Michael.Tuexen@lurchi.franken.de> Mon, 07 April 2014 17:38 UTC

Return-Path: <Michael.Tuexen@lurchi.franken.de>
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 DBB7D1A07F7 for <rtcweb@ietfa.amsl.com>; Mon, 7 Apr 2014 10:38:41 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.561
X-Spam-Level:
X-Spam-Status: No, score=-1.561 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, HELO_EQ_DE=0.35, SPF_HELO_PASS=-0.001, T_RP_MATCHES_RCVD=-0.01] autolearn=no
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 riI_5zhY7JqC for <rtcweb@ietfa.amsl.com>; Mon, 7 Apr 2014 10:38:35 -0700 (PDT)
Received: from mail-n.franken.de (drew.ipv6.franken.de [IPv6:2001:638:a02:a001:20e:cff:fe4a:feaa]) by ietfa.amsl.com (Postfix) with ESMTP id 3243B1A07EF for <rtcweb@ietf.org>; Mon, 7 Apr 2014 10:38:20 -0700 (PDT)
Received: from [192.168.1.200] (p508F3041.dip0.t-ipconnect.de [80.143.48.65]) (Authenticated sender: macmic) by mail-n.franken.de (Postfix) with ESMTP id 84B401C1047EC; Mon, 7 Apr 2014 19:38:12 +0200 (CEST)
Content-Type: text/plain; charset=us-ascii
Mime-Version: 1.0 (Mac OS X Mail 7.2 \(1874\))
From: Michael Tuexen <Michael.Tuexen@lurchi.franken.de>
In-Reply-To: <CABkgnnVG7F_6g1NnGuvk1WSV2jw2=O4e2x6xM5cG9FPkxHeBPA@mail.gmail.com>
Date: Mon, 7 Apr 2014 19:38:09 +0200
Content-Transfer-Encoding: quoted-printable
Message-Id: <7E595777-F510-48A0-87FA-0941621D8B26@lurchi.franken.de>
References: <CABkgnnWWuU63Vd=gw+wrh2ADgVYtQzhoRzRE1sv5azJE=MhWDg@mail.gmail.com> <533F191D.8050109@alum.mit.edu> <CABkgnnVht5EmJ7a2LDh50ivjUdoTpJ8GannQKReBSJbVGQGmgA@mail.gmail.com> <53425BAF.4070105@alvestrand.no> <CABkgnnXKe65-30qkuhkCLmaUYVfe8vrWv9BCJzOvC7KaRwUH=g@mail.gmail.com> <5342DE6F.6040306@alvestrand.no> <CABkgnnVG7F_6g1NnGuvk1WSV2jw2=O4e2x6xM5cG9FPkxHeBPA@mail.gmail.com>
To: Martin Thomson <martin.thomson@gmail.com>
X-Mailer: Apple Mail (2.1874)
Archived-At: http://mailarchive.ietf.org/arch/msg/rtcweb/TyJTJF8C_dxtZFtKzcr-K3VqEA4
Cc: "rtcweb@ietf.org" <rtcweb@ietf.org>
Subject: Re: [rtcweb] Isolating data channels (Re: Asking TLS for help with media isolation)
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: Mon, 07 Apr 2014 17:38:42 -0000

On 07 Apr 2014, at 19:23, Martin Thomson <martin.thomson@gmail.com> wrote:

> On 7 April 2014 10:20, Harald Alvestrand <harald@alvestrand.no> wrote:
>> I was actually thinking "protocol" as in the string that goes into the
>> datachannel setup packets. PPIDs would work too for separating
>> browser-to-brower from app-to-app, but I wasn't thinking of them.
> 
> That would require carving out a space to use right now.  That
> impinges to much on application autonomy for my liking.
> 
>> Yes, data channels do cost something to set up. But we're already paying the
>> DTLS tax in order to set up the keying, so it's "just" another
>> request/response. How many extra round trips does the SCTP setup add?
> 
> 2.
Right now: Correct. But one could optimise the initial handshake...

Best regards
Michael
> 
>> (and to Matthew: At least we wouldn't have *yet* another congestion context to
>> manage, which would be the case with a separate TCP connection. There are
>> always tradeoffs.)
> 
> I'm certain that Matthew wasn't talking about TCP.
> 
> _______________________________________________
> rtcweb mailing list
> rtcweb@ietf.org
> https://www.ietf.org/mailman/listinfo/rtcweb
>