Re: [v6ops] draft-ietf-6man-rfc4291bis prohibiting non-/64 subnets

Pierre Pfister <pierre.pfister@darou.fr> Thu, 23 February 2017 22:44 UTC

Return-Path: <SRS0=0eqy=2E=darou.fr=pierre.pfister@bounces.m4x.org>
X-Original-To: ietf@ietfa.amsl.com
Delivered-To: ietf@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 6CEE2129BD8; Thu, 23 Feb 2017 14:44:00 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -4.2
X-Spam-Level:
X-Spam-Status: No, score=-4.2 tagged_above=-999 required=5 tests=[BAYES_00=-1.9, HEADER_FROM_DIFFERENT_DOMAINS=0.001, RCVD_IN_DNSWL_MED=-2.3, SPF_HELO_PASS=-0.001, SPF_PASS=-0.001, URIBL_BLOCKED=0.001] autolearn=ham autolearn_force=no
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 rEQYbLj2eVLu; Thu, 23 Feb 2017 14:43:57 -0800 (PST)
Received: from mx1.polytechnique.org (mx1.polytechnique.org [129.104.30.34]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id A28BC129BC9; Thu, 23 Feb 2017 14:43:57 -0800 (PST)
Received: from [10.61.217.135] (unknown [173.38.220.58]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ssl.polytechnique.org (Postfix) with ESMTPSA id D46D9564671; Thu, 23 Feb 2017 23:43:53 +0100 (CET)
Content-Type: text/plain; charset="utf-8"
Mime-Version: 1.0 (Mac OS X Mail 10.2 \(3259\))
Subject: Re: [v6ops] draft-ietf-6man-rfc4291bis prohibiting non-/64 subnets
From: Pierre Pfister <pierre.pfister@darou.fr>
In-Reply-To: <CAO42Z2ymnLm9dUNL3doU9+vR0eMzGbr71HQybbibXq9rCObP3A@mail.gmail.com>
Date: Thu, 23 Feb 2017 23:43:52 +0100
Content-Transfer-Encoding: quoted-printable
Message-Id: <21A9AEAE-330D-47F3-88CA-FC845C71AED0@darou.fr>
References: <58AF313D.3020905@foobar.org> <CAO42Z2ymnLm9dUNL3doU9+vR0eMzGbr71HQybbibXq9rCObP3A@mail.gmail.com>
To: Mark Smith <markzzzsmith@gmail.com>
X-Mailer: Apple Mail (2.3259)
X-AV-Checked: ClamAV using ClamSMTP at svoboda.polytechnique.org (Thu Feb 23 23:43:55 2017 +0100 (CET))
Archived-At: <https://mailarchive.ietf.org/arch/msg/ietf/7Oc307grKPOK9lGPTU7sySxdR3Q>
Cc: IPv6 Operations <v6ops@ietf.org>, IETF <ietf@ietf.org>
X-BeenThere: ietf@ietf.org
X-Mailman-Version: 2.1.17
Precedence: list
List-Id: IETF-Discussion <ietf.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/ietf>, <mailto:ietf-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/ietf/>
List-Post: <mailto:ietf@ietf.org>
List-Help: <mailto:ietf-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/ietf>, <mailto:ietf-request@ietf.org?subject=subscribe>
X-List-Received-Date: Thu, 23 Feb 2017 22:44:00 -0000

> Le 23 févr. 2017 à 21:42, Mark Smith <markzzzsmith@gmail.com> a écrit :
> 
> On 24 February 2017 at 06:00, Nick Hilliard <nick@foobar.org> wrote:
>> as it's currently worded, draft-ietf-6man-rfc4291bis seems to prohibit
>> the implementation of any interface netmask != /64:
>> 
>>>                                          However, the Interface ID of
>>>   all unicast addresses, except those that start with the binary value
>>>   000, is required to be 64 bits long.
>> 
> 
> The thing is this is not new text, it has been in RFC4291 for 11
> years. c.f., 2.5.1.

And during those 11 years. Nobody implemented this rule specific to ::/3.

> 
> It can't be changed without invalidating all of the other RFCs that
> have utilised 64 bit identifiers.

Those "other RFCs" have nothing to do with being part of ::/3 or not.
They require an interface identifier of 64 bits long.
The fact that a protocol does not work in some conditions does not invalidate the protocol.
e.g. the fact that SLAAC over Ethernet doesn't work when IID is not 64 doesn't mean
the IID could not be 64 bits long. It just means that under those conditions, SLAAC would not work.
And those conditions are perfectly well defined in those "other RFCs".

- Pierre

> 
>> This has substantial operational consequences in the ipv6 world because
>> if it's implemented as stated, it will cause production ipv6 networks to
>> break.
> 
> Going by the millions of IPv6 deployments now, it has been implemented
> as stated.
> 
>> 
>> The ipv6 operational community may have opinions on the wisdom of
>> mandating new behaviour which would cause their networks to fall over,
> 
> There is and should be no new behaviour in RFC4291bis, it is a tidy up
> to advance it along the standard track.
> 
> 
>> so it would probably be a good idea to notify v6ops@ietf about the
>> existence of this draft so that the folks over there get a look-in
>> before a consensus call is made. As far as I can tell, this notification
>> never happened.
>> 
>> Nick
>> 
>> _______________________________________________
>> v6ops mailing list
>> v6ops@ietf.org
>> https://www.ietf.org/mailman/listinfo/v6ops
> 
> _______________________________________________
> v6ops mailing list
> v6ops@ietf.org
> https://www.ietf.org/mailman/listinfo/v6ops