Re: [ietf-privacy] [Int-area] NAT Reveal / Host Identifiers

Joe Touch <touch@isi.edu> Mon, 09 June 2014 15:31 UTC

Return-Path: <touch@isi.edu>
X-Original-To: ietf-privacy@ietfa.amsl.com
Delivered-To: ietf-privacy@ietfa.amsl.com
Received: from localhost (ietfa.amsl.com [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id F3FC01A01D9; Mon, 9 Jun 2014 08:31:01 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.551
X-Spam-Level:
X-Spam-Status: No, score=-2.551 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, RP_MATCHES_RCVD=-0.651] autolearn=ham
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 18KHlf-nT8kY; Mon, 9 Jun 2014 08:31:01 -0700 (PDT)
Received: from darkstar.isi.edu (darkstar.isi.edu [128.9.128.127]) (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id 08ADC1A0068; Mon, 9 Jun 2014 08:31:01 -0700 (PDT)
Received: from [192.168.1.93] (pool-71-105-87-112.lsanca.dsl-w.verizon.net [71.105.87.112]) (authenticated bits=0) by darkstar.isi.edu (8.13.8/8.13.8) with ESMTP id s59FUUpp009409 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES128-SHA bits=128 verify=NOT); Mon, 9 Jun 2014 08:30:33 -0700 (PDT)
Message-ID: <5395D318.4000907@isi.edu>
Date: Mon, 09 Jun 2014 08:30:32 -0700
From: Joe Touch <touch@isi.edu>
User-Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:24.0) Gecko/20100101 Thunderbird/24.5.0
MIME-Version: 1.0
To: David Singer <singer@apple.com>
References: <E87B771635882B4BA20096B589152EF628724B2C@eusaamb107.ericsson.se> <539016BE.3070008@gmx.net> <53906711.5070406@cs.tcd.ie> <5390CEC9.3000005@isi.edu> <5D2CC7D6-D9E1-49A8-818C-5FB33DC283C0@cisco.com> <5393119F.6050805@cs.tcd.ie> <82A0BCB8-F77C-4C8B-9769-BF4EE2F748A0@isi.edu> <747229F0-D5EB-4262-B14C-46C860F9165C@apple.com>
In-Reply-To: <747229F0-D5EB-4262-B14C-46C860F9165C@apple.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit
X-ISI-4-43-8-MailScanner: Found to be clean
X-MailScanner-From: touch@isi.edu
Archived-At: http://mailarchive.ietf.org/arch/msg/ietf-privacy/d-K1NxLJRmdFTvLkUfOHkdAM4mc
Cc: "ietf-privacy@ietf.org" <ietf-privacy@ietf.org>, Internet Area <int-area@ietf.org>
Subject: Re: [ietf-privacy] [Int-area] NAT Reveal / Host Identifiers
X-BeenThere: ietf-privacy@ietf.org
X-Mailman-Version: 2.1.15
Precedence: list
List-Id: Internet Privacy Discussion List <ietf-privacy.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/ietf-privacy>, <mailto:ietf-privacy-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/ietf-privacy/>
List-Post: <mailto:ietf-privacy@ietf.org>
List-Help: <mailto:ietf-privacy-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/ietf-privacy>, <mailto:ietf-privacy-request@ietf.org?subject=subscribe>
X-List-Received-Date: Mon, 09 Jun 2014 15:31:02 -0000


On 6/9/2014 6:34 AM, David Singer wrote:
>
> On Jun 8, 2014, at 20:26 , Joe Touch <touch@ISI.EDU> wrote:
>
>> 	a NAT hides the host *at the expense* of exposing a router
>
> If I have the energy to do a DoS attack, surely I have the energy to
> traceroute the hosts I know to find a common routing point?

1) ICMPs are often blocked - either at network boundaries or inside 
routers themselves

2) an ICMP tells you only how your packets get to the destination; it 
says nothing about how other traffic gets there or the return path

A NAT address tells you both directions and *cannot* be hidden except by 
another NAT along the same path.

Joe

>
> David Singer
> Manager, Software Standards, Apple Inc.
>