IETF Logo Mail Archive

Re: Is Fragmentation at IP layer even needed ?

Joe Touch <touch@isi.edu> Mon, 15 February 2016 04:00 UTC

Return-Path: <touch@isi.edu>
X-Original-To: ietf@ietfa.amsl.com
Delivered-To: ietf@ietfa.amsl.com
Received: from localhost (ietfa.amsl.com [127.0.0.1]) by ietfa.amsl.com (Postfix) with ESMTP id BACF41B2DC2 for <ietf@ietfa.amsl.com>; Sun, 14 Feb 2016 20:00:35 -0800 (PST)
X-Virus-Scanned: amavisd-new at amsl.com
X-Spam-Flag: NO
X-Spam-Score: -5.007
X-Spam-Level:
X-Spam-Status: No, score=-5.007 tagged_above=-999 required=5 tests=[BAYES_40=-0.001, RCVD_IN_DNSWL_HI=-5, RP_MATCHES_RCVD=-0.006] autolearn=ham
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 IHDCd16JA8rB for <ietf@ietfa.amsl.com>; Sun, 14 Feb 2016 20:00:34 -0800 (PST)
Received: from boreas.isi.edu (boreas.isi.edu [128.9.160.161]) (using TLSv1 with cipher ECDHE-RSA-AES128-SHA (128/128 bits)) (No client certificate requested) by ietfa.amsl.com (Postfix) with ESMTPS id E08071B2DC1 for <ietf@ietf.org>; Sun, 14 Feb 2016 20:00:34 -0800 (PST)
Received: from [192.168.1.189] (cpe-172-250-251-17.socal.res.rr.com [172.250.251.17]) (authenticated bits=0) by boreas.isi.edu (8.13.8/8.13.8) with ESMTP id u1F40IUI016263 (version=TLSv1/SSLv3 cipher=DHE-RSA-AES128-SHA bits=128 verify=NOT); Sun, 14 Feb 2016 20:00:19 -0800 (PST)
Subject: Re: Is Fragmentation at IP layer even needed ?
To: Masataka Ohta <mohta@necom830.hpcl.titech.ac.jp>, ietf@ietf.org
References: <CAOJ6w=EvzE3dM4Y2mFFR=9YyPBdmFu_jkF4-42LjkdbRd3yz_w@mail.gmail.com> <BLUPR05MB1985F5F2BB3118362C67B921AED50@BLUPR05MB1985.namprd05.prod.outlook.com> <20160208200943.A615941B5B96@rock.dv.isc.org> <CAMm+LwgLoYpQ1TNOTOuJzh+cu+GyRBf9=y_K7K35boQ9WcZKjA@mail.gmail.com> <56B92A96.9050200@si6networks.com> <CAMm+LwifTXvVd1mPZOfcOOR03Fnj-82H9aDVS01=wGezePtnXw@mail.gmail.com> <56BA4BC7.1010002@isi.edu> <CAMm+Lwi-n=be4AWGibs+Zq9egYw5pSDmPGb-4P0LDEcX1E6osA@mail.gmail.com> <56BA68CE.7090304@isi.edu> <CAMm+LwiM2sFUeejgJZe650UQbVHrh7EHrEF2omvPrZJPodgJLA@mail.gmail.com> <56BA739D.7060309@isi.edu> <CAMm+Lwij1dOkK0b2ZnJiPMtba=wc823WgYjqw0iwAApa3KBYcg@mail.gmail.com> <56BA95C7.8060109@isi.edu> <56BAD6CC.2030209@necom830.hpcl.titech.ac.jp> <56BBAAF7.6020903@isi.edu> <56BC9516.6050305@necom830.hpcl.titech.ac.jp> <56BCCBB4.4050909@isi.edu> <56BCF514.6040401@necom830.hpcl.titech.ac.jp> <56BE23F0.4090403@isi.edu> <56BFD7B3.9080505@necom830.hpcl.titech.ac.jp>
From: Joe Touch <touch@isi.edu>
X-Enigmail-Draft-Status: N1110
Message-ID: <56C14D50.4040802@isi.edu>
Date: Sun, 14 Feb 2016 20:00:16 -0800
User-Agent: Mozilla/5.0 (Windows NT 6.3; WOW64; rv:38.0) Gecko/20100101 Thunderbird/38.5.1
MIME-Version: 1.0
In-Reply-To: <56BFD7B3.9080505@necom830.hpcl.titech.ac.jp>
Content-Type: text/plain; charset="iso-2022-jp"
Content-Transfer-Encoding: 7bit
X-ISI-4-43-8-MailScanner: Found to be clean
X-MailScanner-From: touch@isi.edu
Archived-At: <http://mailarchive.ietf.org/arch/msg/ietf/Wez5rdc64ZBi72CDJ7mKz7veOj0>
X-BeenThere: ietf@ietf.org
X-Mailman-Version: 2.1.15
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: Mon, 15 Feb 2016 04:00:35 -0000


On 2/13/2016 5:26 PM, Masataka Ohta wrote:
> QoS (not CoS but real QoS) capable routers must inspect L4.

That must be why there are QoS indicators in the L4 header.

Oh, wait - those are in L3 (RFC2474 and its successors).

Yes, layering is a difficult concept.

Joe

v2.23.0 | Report a Bug | By Email