IETF Logo Mail Archive

RE: Why has RFC 4941 been designed in such a way, that it might causeaddress conflicts?

"Hemant Singh (shemant)" <shemant@cisco.com> Sun, 20 March 2011 23:08 UTC

Return-Path: <shemant@cisco.com>
X-Original-To: ipv6@core3.amsl.com
Delivered-To: ipv6@core3.amsl.com
Received: from localhost (localhost [127.0.0.1]) by core3.amsl.com (Postfix) with ESMTP id 0E8BD3A6A07 for <ipv6@core3.amsl.com>; Sun, 20 Mar 2011 16:08:01 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -10.423
X-Spam-Level:
X-Spam-Status: No, score=-10.423 tagged_above=-999 required=5 tests=[AWL=-0.424, BAYES_00=-2.599, J_CHICKENPOX_13=0.6, RCVD_IN_DNSWL_HI=-8]
Received: from mail.ietf.org ([64.170.98.32]) by localhost (core3.amsl.com [127.0.0.1]) (amavisd-new, port 10024) with ESMTP id 6kc7+zqoU5Ld for <ipv6@core3.amsl.com>; Sun, 20 Mar 2011 16:08:00 -0700 (PDT)
Received: from sj-iport-1.cisco.com (sj-iport-1.cisco.com [171.71.176.70]) by core3.amsl.com (Postfix) with ESMTP id 54A5D3A69CD for <ipv6@ietf.org>; Sun, 20 Mar 2011 16:07:58 -0700 (PDT)
DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=cisco.com; i=shemant@cisco.com; l=2382; q=dns/txt; s=iport; t=1300662570; x=1301872170; h=mime-version:content-transfer-encoding:subject:date: message-id:in-reply-to:references:from:to:cc; bh=JEkeVUek1J1cmjzqD64ONs+DOWD7A5RJaaGYEcppLVY=; b=WVa7Jo/3diTKEa7H0EgGLEJeI12mTfRjRs6vBxDwaJf7g3+EpL7nuwJz XokXtGNE3Zma3iTBTDR0rw+NnyLewLjEEb9c3iU4n23FXnX2CeKhxIqvv YPA0yj66N98mQeHGYsvokS5t6p9Uv9tJyrC3pQ8iyXP3F713O0mDdOZq7 g=;
X-IronPort-Anti-Spam-Filtered: true
X-IronPort-Anti-Spam-Result: AvQAAHIlhk2tJXG8/2dsb2JhbACERZNvjF1ed6N/iyiDBoxmgSeDRXcEhTOLC4Mg
X-IronPort-AV: E=Sophos;i="4.63,216,1299456000"; d="scan'208";a="416312436"
Received: from rcdn-core2-1.cisco.com ([173.37.113.188]) by sj-iport-1.cisco.com with ESMTP; 20 Mar 2011 23:09:30 +0000
Received: from xbh-rcd-201.cisco.com (xbh-rcd-201.cisco.com [72.163.62.200]) by rcdn-core2-1.cisco.com (8.14.3/8.14.3) with ESMTP id p2KN9UQP029144; Sun, 20 Mar 2011 23:09:30 GMT
Received: from xmb-rcd-109.cisco.com ([72.163.62.151]) by xbh-rcd-201.cisco.com with Microsoft SMTPSVC(6.0.3790.4675); Sun, 20 Mar 2011 18:09:30 -0500
X-MimeOLE: Produced By Microsoft Exchange V6.5
Content-class: urn:content-classes:message
MIME-Version: 1.0
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: base64
Subject: RE: Why has RFC 4941 been designed in such a way, that it might causeaddress conflicts?
Date: Sun, 20 Mar 2011 18:09:27 -0500
Message-ID: <5B6B2B64C9FE2A489045EEEADDAFF2C3010D2B39@XMB-RCD-109.cisco.com>
In-Reply-To: <4D868457.5060504@gmail.com>
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
Thread-Topic: Why has RFC 4941 been designed in such a way, that it might causeaddress conflicts?
Thread-Index: AcvnUQGk0zeH7K9jSN6Ye4GDL53qGQAAENGg
References: <C744C51B-F2B0-4137-B39F-54B8D62F1C97@equinux.de> <E7CFEDBC-5048-413E-93C9-DBF79B4FC238@apple.com> <E8CD61BF-827E-4A83-AA63-275D0CCB0B53@equinux.de><35A891E0-9BA1-4694-AFA3-C6C46C8F3625@apple.com> <4D7FEE26.9060502@gmail.com> <5B6B2B64C9FE2A489045EEEADDAFF2C3010D2B1F@XMB-RCD-109.cisco.com> <4D868457.5060504@gmail.com>
From: "Hemant Singh (shemant)" <shemant@cisco.com>
To: Brian E Carpenter <brian.e.carpenter@gmail.com>
X-OriginalArrivalTime: 20 Mar 2011 23:09:30.0054 (UTC) FILETIME=[DDD9EE60:01CBE753]
Cc: ipv6@ietf.org
X-BeenThere: ipv6@ietf.org
X-Mailman-Version: 2.1.9
Precedence: list
List-Id: "IPv6 Maintenance Working Group \(6man\)" <ipv6.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/listinfo/ipv6>, <mailto:ipv6-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/ipv6>
List-Post: <mailto:ipv6@ietf.org>
List-Help: <mailto:ipv6-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/ipv6>, <mailto:ipv6-request@ietf.org?subject=subscribe>
X-List-Received-Date: Sun, 20 Mar 2011 23:08:01 -0000

-----Original Message-----
From: Brian E Carpenter [mailto:brian.e.carpenter@gmail.com] 
Sent: Sunday, March 20, 2011 6:49 PM
To: Hemant Singh (shemant)
Cc: james woodyatt; ipv6@ietf.org
Subject: Re: Why has RFC 4941 been designed in such a way, that it might causeaddress conflicts?


>Good idea, where's the wiki?

Ah, none that I know of.  Also, I am only catching up to 6man email this weekend being busy in the week with v6ops emails.  If a wiki does not exist for such issues, we could start one.  Since our cable IPv6 home devices such as cable modems and IPv6 CE Routers (standalone or combined inside a modem) are assumed to provide no console, we have specified use of a DAD Proxy at the first-hop IPv6 router.  This first-hop router is also the access concentrator (a CMTS - Cable Modem Termination System) for cable broadband.  Note since the cable network is an end-to-end IP network, it is easier for cable to specify support for DAD Proxy at the CMTS.  DSL which is not end-to-end at the IP layer has more issues to deal with.  The reason is that a SP has console access to the CMTS and if the CMTS supports a DAD Proxy, the SP at least knows which home the failure has occurred in and take some action.  Without the CMTS supporting DAD proxy, the DAD failure for a modem or CE festers for an error with the modem or CE dead in the water.   Of course, the home customer would call the SP in such a situation but it's better for the SP to be proactive to catch the error before any home user calls.  

It's also interesting that even when the SP has detected a DAD Duplicate, what does the SP do besides shutting down one of the two nodes that clashed for the same IPv6 link-local address.  

Thanks,

Hemant

v2.23.0 | Report a Bug | By Email