IETF Logo Mail Archive

Re: [Softwires] Proposed Unified Address Mapping for encapsulation and double-translation

Rémi Després <despres.remi@free.fr> Mon, 17 October 2011 16:21 UTC

Return-Path: <despres.remi@free.fr>
X-Original-To: softwires@ietfa.amsl.com
Delivered-To: softwires@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 26BB321F8B0D for <softwires@ietfa.amsl.com>; Mon, 17 Oct 2011 09:21:36 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -2.3
X-Spam-Level:
X-Spam-Status: No, score=-2.3 tagged_above=-999 required=5 tests=[AWL=-0.000, BAYES_00=-2.599, HTML_MESSAGE=0.001, MIME_8BIT_HEADER=0.3, NO_RELAYS=-0.001]
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 NlH4+JwCEM3p for <softwires@ietfa.amsl.com>; Mon, 17 Oct 2011 09:21:35 -0700 (PDT)
Received: from smtp1-g21.free.fr (unknown [IPv6:2a01:e0c:1:1599::10]) by ietfa.amsl.com (Postfix) with ESMTP id 67A5D21F8797 for <softwires@ietf.org>; Mon, 17 Oct 2011 09:21:26 -0700 (PDT)
Received: from [IPv6:2a01:e35:8a6d:d900:129a:ddff:fe6b:c6fb] (unknown [IPv6:2a01:e35:8a6d:d900:129a:ddff:fe6b:c6fb]) by smtp1-g21.free.fr (Postfix) with ESMTP id 21E49940525; Mon, 17 Oct 2011 18:21:20 +0200 (CEST)
Mime-Version: 1.0 (Apple Message framework v1084)
Content-Type: multipart/alternative; boundary="Apple-Mail-3--888620067"
From: Rémi Després <despres.remi@free.fr>
In-Reply-To: <CAFUBMqVni_GNqmEx-FwzNUKUD1x2hN=xoe7Zc9pre4rfmGBWRw@mail.gmail.com>
Date: Mon, 17 Oct 2011 18:21:19 +0200
Message-Id: <C87E17E8-8686-4D01-939E-E6C7C3E5DF58@free.fr>
References: <F259BF79-B3C9-4434-AAC4-9F84B8D9A0FA@laposte.net> <CAM+vMER2CBTpYOhcu63th7AJejCJ4sv0_GqeiZmwHVHEEeW1WA@mail.gmail.com> <0C2B5428-98D4-4F67-B18D-9ACA946A68E7@laposte.net> <CABv173VeFd5DVLm5XvX5+PTgW2biQpUCnW=Z7EXHj7EDG-5LUg@mail.gmail.com> <CAM+vMERXwqJWobpUsk=Pq6OkubBSCc8QFdNsRgMSyzf+1e8SgQ@mail.gmail.com> <CAFUBMqVkMQ89tffeGcBT5mJpz56mrvabe0pjdiJ-ia7XfoVhYw@mail.gmail.com> <CABv173U4wOBYBjM+kaCfHM1ksNPSk1WW_JvMTf1Y1=b_-X=jrg@mail.gmail.com> <CAM+vMETVf763VWLLCHy072NcHTi0v=cMOyjQ+u2HHa5SwiFF_A@mail.gmail.com> <CAFUBMqX01bLG4Rkn=zvT9o4Q4UF3sGCqEGd7AD0aW-ZkC9AS6w@mail.gmail.com> <CAM+vMET5J4XVbrKR9zdHXN8LqhBYJ=psYMoSXBNFzwZVUkE0YA@mail.gmail.com> <14AB4609-752F-44E2-BE75-EB414CC2ACFA@ipinfusion.com> <CAFUBMqVni_GNqmEx-FwzNUKUD1x2hN=xoe7Zc9pre4rfmGBWRw@mail.gmail.com>
To: Maoke <fibrib@gmail.com>
X-Mailer: Apple Mail (2.1084)
Cc: Softwires-wg <softwires@ietf.org>
Subject: Re: [Softwires] Proposed Unified Address Mapping for encapsulation and double-translation
X-BeenThere: softwires@ietf.org
X-Mailman-Version: 2.1.12
Precedence: list
List-Id: softwires wg discussion list <softwires.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/softwires>, <mailto:softwires-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/softwires>
List-Post: <mailto:softwires@ietf.org>
List-Help: <mailto:softwires-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/softwires>, <mailto:softwires-request@ietf.org?subject=subscribe>
X-List-Received-Date: Mon, 17 Oct 2011 16:21:36 -0000

Hi Maoke,

On 2011/10/12, you wrote:
"... considering the double translation is a case of translation. it is possible that a src host with an IPv4-translatable IPv6 address generates a fragment header with a 32-bit identifier happening to have the first 16 bit as either 0x8000 or 0x0000, making a fake D bit in your current proposal."

An important point is that the IP identifier needs to be unique ONLY for each <SRC, DST> pair.
If 4rd addresses are deterministically recognizable (with the V octet in bits 64-71), there is no risk of confusion with an IP identification generated for another purpose than 4rd.

Hope it clarifies.

Cheers,
RD

v2.23.0 | Report a Bug | By Email