Re: [Int-area] WG Adoption Call: IP Fragmentation Considered Fragile

Ole Troan <otroan@employees.org> Tue, 31 July 2018 12:37 UTC

Return-Path: <otroan@employees.org>
X-Original-To: int-area@ietfa.amsl.com
Delivered-To: int-area@ietfa.amsl.com
Received: from localhost (localhost [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id 0B2FF129AB8; Tue, 31 Jul 2018 05:37:04 -0700 (PDT)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -0.001
X-Spam-Level:
X-Spam-Status: No, score=-0.001 tagged_above=-999 required=5 tests=[RCVD_IN_DNSWL_NONE=-0.0001, SPF_PASS=-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 OR86QGczfq2p; Tue, 31 Jul 2018 05:37:02 -0700 (PDT)
Received: from accordion.employees.org (accordion.employees.org [198.137.202.74]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id B50A7128CFD; Tue, 31 Jul 2018 05:37:02 -0700 (PDT)
Received: from astfgl.hanazo.no (unknown [173.38.220.57]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by accordion.employees.org (Postfix) with ESMTPSA id B62042D527D; Tue, 31 Jul 2018 12:28:02 +0000 (UTC)
Received: from [IPv6:::1] (localhost [IPv6:::1]) by astfgl.hanazo.no (Postfix) with ESMTP id 22F572214A3; Tue, 31 Jul 2018 14:28:00 +0200 (CEST)
Content-Type: text/plain; charset="utf-8"
Mime-Version: 1.0 (Mac OS X Mail 11.5 \(3445.9.1\))
From: Ole Troan <otroan@employees.org>
In-Reply-To: <240E40E2-81F9-4FAB-A271-825BD7AC6073@strayalpha.com>
Date: Tue, 31 Jul 2018 14:27:59 +0200
Cc: Tom Herbert <tom@herbertland.com>, "internet-area@ietf.org" <int-area@ietf.org>, intarea-chairs@ietf.org
Content-Transfer-Encoding: quoted-printable
Message-Id: <96EB5285-E0F6-43BB-A6CE-B087A4F8DF62@employees.org>
References: <F227637E-B12D-45AA-AD69-74C947409012@ericsson.com> <0466770D-C8CA-49BB-AC10-5805CFDFB165@strayalpha.com> <6EDF0F79-C8F3-4F05-8442-FF55576ADDD0@employees.org> <alpine.DEB.2.20.1807271530280.14354@uplift.swm.pp.se> <CALx6S35LthDLRry7k-pF8KSoX4BXBA8kyArOpDUAcJMDCoLQpQ@mail.gmail.com> <alpine.DEB.2.20.1807280811540.14354@uplift.swm.pp.se> <8640DCF6-A525-4CF7-A89D-2DEDBF0FADC8@strayalpha.com> <FFF1C23B-7A24-46BC-929E-DD56C77D69A2@employees.org> <A248CA44-B568-4CB9-B450-067B1845AF9B@strayalpha.com> <CALx6S36w=5J0-=JQqrX0_PR7254V0HrhJct7oomPKdxSOSU43w@mail.gmail.com> <2872BF43-20AA-4179-9269-9C4FE6F5986B@strayalpha.com> <CALx6S35VidDr1uTGCHeb3Dcc0qF3O8Lz0vvV-XKPfbY057n6XA@mail.gmail.com> <cd34a1e8da6ff4bbf5b20875827d2a09@strayalpha.com> <CALx6S348jLsnHG3gp-mh9d4KJ1bROT3OcVz=XjwVgpv1aSsi_w@mail.gmail.com> <c271e9501b381c9be6ac1f3a0095a1d9@strayalpha.com> <CALx6S35DRCEjS5qaVkj2_FJzNumrkSfCZmoSJLueqqZs+pm9gw@mail.gmail.com> <240E40E2-81F9-4FAB-A271-825BD7AC6073@strayalpha.com>
To: Joe Touch <touch@strayalpha.com>
X-Mailer: Apple Mail (2.3445.9.1)
Archived-At: <https://mailarchive.ietf.org/arch/msg/int-area/B4wbKdXMCVaU5kVqGtlggPhIwvc>
Subject: Re: [Int-area] WG Adoption Call: IP Fragmentation Considered Fragile
X-BeenThere: int-area@ietf.org
X-Mailman-Version: 2.1.27
Precedence: list
List-Id: IETF Internet Area Mailing List <int-area.ietf.org>
List-Unsubscribe: <https://www.ietf.org/mailman/options/int-area>, <mailto:int-area-request@ietf.org?subject=unsubscribe>
List-Archive: <https://mailarchive.ietf.org/arch/browse/int-area/>
List-Post: <mailto:int-area@ietf.org>
List-Help: <mailto:int-area-request@ietf.org?subject=help>
List-Subscribe: <https://www.ietf.org/mailman/listinfo/int-area>, <mailto:int-area-request@ietf.org?subject=subscribe>
X-List-Received-Date: Tue, 31 Jul 2018 12:37:04 -0000

Joe,

>> The need for fragmentation cannot be completely
>> eliminated and we do need it to work. Devices that do things to
>> prevent correct operation still need to be fixed, and it would be
>> productive for the draft to include statements on how some of the
>> sub-problems problems can be fixed (like using flow label for ECMP
>> instead of ports).
> 
> On that we agree. That’s my key concern - how to do this in a way that doesn’t effectively kill off IP fragmentation for the rest of us.

For IPv4 it’s an unfortunate side-effect of the fact that we are out of IPv4 addresses. As we continue to increase the ratio of users per IPv4 address, IPv4 fragmentation, or any protocol that isn’t TCP or UDP are not going to work well in the public IPv4 Internet.
IPv4 Internet Architecture is evolving as a consequence of address run-out. I think we’ve pretty much explored the solution space for IPv4 sharing mechanisms, so I think you just have to accept this new and unimproved (sic) IPv4 Internet architecture.

Cheers,
Ole