Re: [rtcweb] Requiring ICE for RTC calls

Matthew Kaufman <matthew.kaufman@skype.net> Mon, 26 September 2011 15:47 UTC

Return-Path: <matthew.kaufman@skype.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 A0EE121F8C10 for <rtcweb@ietfa.amsl.com>; Mon, 26 Sep 2011 08:47:21 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -5.226
X-Spam-Level:
X-Spam-Status: No, score=-5.226 tagged_above=-999 required=5 tests=[AWL=1.073, BAYES_00=-2.599, MIME_8BIT_HEADER=0.3, RCVD_IN_DNSWL_MED=-4]
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 nuN0l0zvoBCo for <rtcweb@ietfa.amsl.com>; Mon, 26 Sep 2011 08:47:20 -0700 (PDT)
Received: from mx.skype.net (mx.skype.net [78.141.177.88]) by ietfa.amsl.com (Postfix) with ESMTP id D850F21F8C0F for <rtcweb@ietf.org>; Mon, 26 Sep 2011 08:47:19 -0700 (PDT)
Received: from mx.skype.net (localhost [127.0.0.1]) by mx.skype.net (Postfix) with ESMTP id 90A9416F6; Mon, 26 Sep 2011 17:50:00 +0200 (CEST)
DKIM-Signature: v=1; a=rsa-sha1; c=relaxed; d=skype.net; h=message-id :date:from:mime-version:to:cc:subject:references:in-reply-to :content-type:content-transfer-encoding; s=mx; bh=Y/4AR+leWLFNJ6 qhXvyFEPoTx88=; b=fHikMOP0c/AQycX1EVOqZmL3umPlIcIqus4uM0ds0QScmN MOcd2E9yn4OxaZw9fiMPTPh41eXhnsYmm3YbP5FWSoroktivFG1y40bo6lG4mdfv KYRcaJD63hYs3FgBcy6WNhdnagbEdq68KLEPGJAgVJCdGpfVcrki/z4Bcjn54=
DomainKey-Signature: a=rsa-sha1; c=nofws; d=skype.net; h=message-id:date:from :mime-version:to:cc:subject:references:in-reply-to:content-type: content-transfer-encoding; q=dns; s=mx; b=ot3BtEVuY8/QA81bIZjTxB 3DLxoQU7GyIS02o8CqskgZkO344CKbGRTi8iVNxHH9izpmf1h8ZEQAMJ47krF+9j DC/IgYKtrYZrqH4LLoUtoz1GWqaFMaYpzb6GAs0SwFyCyaJ0zCDUQMfhVaQlX7An PpJM6iwWXw5Y7ZaILBw2M=
Received: from zimbra.skype.net (zimbra.skype.net [78.141.177.82]) by mx.skype.net (Postfix) with ESMTP id 8F04D7F6; Mon, 26 Sep 2011 17:50:00 +0200 (CEST)
Received: from localhost (localhost [127.0.0.1]) by zimbra.skype.net (Postfix) with ESMTP id 5BE6C1672681; Mon, 26 Sep 2011 17:50:00 +0200 (CEST)
X-Virus-Scanned: amavisd-new at lu2-zimbra.skype.net
Received: from zimbra.skype.net ([127.0.0.1]) by localhost (zimbra.skype.net [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id S6oPLmdpDBmH; Mon, 26 Sep 2011 17:49:59 +0200 (CEST)
Received: from [10.10.155.2] (unknown [198.202.199.254]) by zimbra.skype.net (Postfix) with ESMTPSA id A05231672683; Mon, 26 Sep 2011 17:49:58 +0200 (CEST)
Message-ID: <4E809EE6.2050702@skype.net>
Date: Mon, 26 Sep 2011 08:48:54 -0700
From: Matthew Kaufman <matthew.kaufman@skype.net>
User-Agent: Mozilla/5.0 (Windows NT 5.1; rv:6.0.2) Gecko/20110902 Thunderbird/6.0.2
MIME-Version: 1.0
To: =?UTF-8?B?ScOxYWtpIEJheiBDYXN0aWxsbw==?= <ibc@aliax.net>
References: <CAD5OKxtNjmWBz92bRuxka7e-BUpTPgVUvr3ahJGpmZ-U5nuPbQ@mail.gmail.com> <CAD6AjGSmz5T_F+SK2EoBQm6T-iRKp7dd4j8ZAF5JKdbbyomZQA@mail.gmail.com> <CALiegfmO54HC+g9L_DYn4jtXAAbLEvS++qxKa6TNrLDREs9SeA@mail.gmail.com> <4E80984A.903@skype.net> <CALiegfmyvTb57WVooKryS-ubfcg+w5gZ+zfO1zzBLn3609AzaA@mail.gmail.com>
In-Reply-To: <CALiegfmyvTb57WVooKryS-ubfcg+w5gZ+zfO1zzBLn3609AzaA@mail.gmail.com>
Content-Type: text/plain; charset=UTF-8; format=flowed
Content-Transfer-Encoding: quoted-printable
Cc: Randell Jesup <randell-ietf@jesup.org>, rtcweb@ietf.org
Subject: Re: [rtcweb] Requiring ICE for RTC calls
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: Mon, 26 Sep 2011 15:47:21 -0000

On 9/26/2011 8:29 AM, Iñaki Baz Castillo wrote:
> 2011/9/26 Matthew Kaufman<matthew.kaufman@skype.net>et>:
>> For example, an evil overlord that creates a web site for allowing its
>> clients to attack systems behind a firewall could relax those requirements
>> and not mandate ICE/SRTP when opening arbitrary connections to systems
>> behind said firewall.
>>
>> The "configuration" must be retrieved by the WebRTC client *from the system
>> it will be sending traffic to*... the best format we have for that is to
>> send a (rate-limited) STUN connectivity check with short-term credentials
>> and see if it is replied to properly. That's how ICE works.
> I understand your points and I agree. That would be the perfect scenario.

That would be the only scenario that is safe enough to ship in a browser.

> But I'm worried about the price to pay for these security constrains
> (no interoperability with 95% of SIP-PSTN providers within next 3-5
> years).

The alternative is that you don't ship anything in the browser, because 
the browser *cannot* become an attack vector as a result of adding this 
feature.

And "interoperability with SIP-PSTN providers" is only relevant if you 
are trying to turn the browser into another phone. We have enough 
phones. What we don't have are new real-time communication experiences 
that can only be created within this environment.

Matthew Kaufman