Re: [Autoconf] Autoconf addressing model

"Teco Boot" <teco@inf-net.nl> Thu, 05 March 2009 14:04 UTC

Return-Path: <teco@inf-net.nl>
X-Original-To: autoconf@core3.amsl.com
Delivered-To: autoconf@core3.amsl.com
Received: from localhost (localhost [127.0.0.1]) by core3.amsl.com (Postfix) with ESMTP id 4A3B328C285 for <autoconf@core3.amsl.com>; Thu, 5 Mar 2009 06:04:13 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -1.747
X-Spam-Level:
X-Spam-Status: No, score=-1.747 tagged_above=-999 required=5 tests=[AWL=0.299, BAYES_00=-2.599, HELO_MISMATCH_COM=0.553]
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 fB++IGMw9758 for <autoconf@core3.amsl.com>; Thu, 5 Mar 2009 06:04:12 -0800 (PST)
Received: from cpsmtpo-eml05.kpnxchange.com (cpsmtpo-eml05.KPNXCHANGE.COM [213.75.38.154]) by core3.amsl.com (Postfix) with ESMTP id 435B728C297 for <autoconf@ietf.org>; Thu, 5 Mar 2009 06:04:12 -0800 (PST)
Received: from cpsmtp-eml104.kpnxchange.com ([213.75.84.104]) by cpsmtpo-eml05.kpnxchange.com with Microsoft SMTPSVC(6.0.3790.3959); Thu, 5 Mar 2009 15:04:40 +0100
Received: from M90Teco ([86.83.9.22]) by cpsmtp-eml104.kpnxchange.com with Microsoft SMTPSVC(6.0.3790.3959); Thu, 5 Mar 2009 15:04:40 +0100
From: "Teco Boot" <teco@inf-net.nl>
To: "'Alexandru Petrescu'" <alexandru.petrescu@gmail.com>
References: <499F0BA7.90501@piuha.net> <49A7E58C.2020303@gmail.com> <007201c99903$c4182c80$4c488580$@nl><49A82E55.10208@gmail.com> <007b01c99911$907facf0$b17f06d0$@nl><49A8471E.6090506@gmail.com> <009501c99920$92154340$b63fc9c0$@nl><49A944FF.9000102@gmail.com> <003001c99b2c$a3fcf4a0$ebf6dde0$@nl><49AD5184.6080300@gmail.com> <000101c99c3c$3121a870$9364f950$@nl><49AD9760.3080909@gmail.com> <49AD98D4.3@earthlink.net><49AD9EA8.6040803@gmail.com> <49ADA17B.9040600@earthlink.net><49ADAF7C.1050509@gmail.com> <49ADB9FB.6050600@earthlink.net> <49AE3A3A.5000305@gmail.com> <7FB7EE0A621BA44B8B69E5F0A09DC76407B5D783@xmb-rtp-208.amer.cisco.com> <49AE9827.5090309@gmail.com> <7FB7EE0A621BA44B8B69E5F0A09DC76407B5D803@xmb-rtp-208.amer.cisco.com> <49AEBA6D.7030903@gmail.com> <7FB7EE0A621BA44B8B69E5F0A09DC76407B5DB1F@xmb-rtp-208.amer.cisco.com> <49AF97FA.70200! 07@gmail.com> <002201c99d76$017d4b20$0477e160$@nl> <49AFAA15.9! 060905@gmail.com> <003a01c99d8e$f47ba2f0$dd72e8d0$@nl> <49AFD85E.504030 1@gmail.com>
In-Reply-To: <49AFD85E.5040301@gmail.com>
Date: Thu, 5 Mar 2009 15:04:41 +0100
Message-ID: <004a01c99d9b$542e1e10$fc8a5a30$@nl>
MIME-Version: 1.0
Content-Type: text/plain; charset="us-ascii"
Content-Transfer-Encoding: 7bit
X-Mailer: Microsoft Office Outlook 12.0
Thread-Index: AcmdmTFVTbvru92PSDSXjNMq4KbBrAAAQzQQ
Content-Language: nl
X-OriginalArrivalTime: 05 Mar 2009 14:04:40.0749 (UTC) FILETIME=[53C215D0:01C99D9B]
Cc: autoconf@ietf.org
Subject: Re: [Autoconf] Autoconf addressing model
X-BeenThere: autoconf@ietf.org
X-Mailman-Version: 2.1.9
Precedence: list
List-Id: Ad-Hoc Network Autoconfiguration WG discussion list <autoconf.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/listinfo/autoconf>, <mailto:autoconf-request@ietf.org?subject=unsubscribe>
List-Archive: <http://www.ietf.org/mail-archive/web/autoconf>
List-Post: <mailto:autoconf@ietf.org>
List-Help: <mailto:autoconf-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/autoconf>, <mailto:autoconf-request@ietf.org?subject=subscribe>
X-List-Received-Date: Thu, 05 Mar 2009 14:04:13 -0000

Hi Alex,


|> So the following topology is valid:
|>
|> +----------+                        +----------+
|> |          |fe80::1/64              |          |
|> |          +========================+          |
|> | router 1 |              fe80::2/64| router 2 |
|> |          |fe80::1/64              |          |
|> |          +========================+          |
|> |          |              fe80::2/64|          |
|> +----------+                        +----------+
|>
|> Agreed on this?
|
|Agreed.  But why /64?  An address is /128, and the link-local address'
|prefix is /10.

I used address-prefix format (RFC4291).

And RFC2464:

5.  Link-Local Addresses
   The IPv6 link-local address [AARCH] for an Ethernet interface is
   formed by appending the Interface Identifier, as defined above, to
   the prefix FE80::/64.

The 54 bits following 1111111011 are zero. There is little difference
between FE80::/10 and FE80::/64. On Ethernet, it is the latter.



|> I repeated the test with the link local addresses. Here also, I
|> experienced no problems. This is because there are two links with
|> exactly the same address pairs (an advantage to use same LL addresses
|> on all interfaces).
|
|Demonstrating the advantage of loopback0 vs eth0 would have implied that
|you start OSPFv3 on eth0 instead of loopback0 and that it would have
|crashed.

My routing protocols do not crash. I told you before.



|But even then, I'm sure there may exist OSPFv3 implementation which
|would not crash when running over eth0 and ifconfig down eth0.
|
|In this sense, if the loopback0 interface is a solution to crashing
|OSPFv3-over-eth0, then it is an implementation solution. Some
|implementations do, others don't.

You totally missed the point.



Teco.