[Ips] FW: RFC 4963 on IPv4 Reassembly Errors at High Data Rates

Black_David@emc.com Mon, 30 July 2007 01:56 UTC

Return-path: <ips-bounces@ietf.org>
Received: from [127.0.0.1] (helo=stiedprmman1.va.neustar.com) by megatron.ietf.org with esmtp (Exim 4.43) id 1IFKV6-0004g6-ET; Sun, 29 Jul 2007 21:56:48 -0400
Received: from ips by megatron.ietf.org with local (Exim 4.43) id 1IFKV4-0004fR-KA for ips-confirm+ok@megatron.ietf.org; Sun, 29 Jul 2007 21:56:46 -0400
Received: from [10.91.34.44] (helo=ietf-mx.ietf.org) by megatron.ietf.org with esmtp (Exim 4.43) id 1IFKV4-0004f0-9H for ips@ietf.org; Sun, 29 Jul 2007 21:56:46 -0400
Received: from mexforward.lss.emc.com ([128.222.32.20]) by ietf-mx.ietf.org with esmtp (Exim 4.43) id 1IFKV3-0003k3-GC for ips@ietf.org; Sun, 29 Jul 2007 21:56:46 -0400
Received: from mailhub.lss.emc.com (nagas.lss.emc.com [10.254.144.11]) by mexforward.lss.emc.com (Switch-3.2.5/Switch-3.1.7) with ESMTP id l6U1uiip023443 for <ips@ietf.org>; Sun, 29 Jul 2007 21:56:44 -0400 (EDT)
Received: from corpussmtp3.corp.emc.com (corpussmtp3.corp.emc.com [10.254.64.53]) by mailhub.lss.emc.com (Switch-3.2.5/Switch-3.1.7) with ESMTP id l6U1tx1O006642 for <ips@ietf.org>; Sun, 29 Jul 2007 21:56:42 -0400 (EDT)
From: Black_David@emc.com
Received: from CORPUSMX20A.corp.emc.com ([128.221.62.12]) by corpussmtp3.corp.emc.com with Microsoft SMTPSVC(6.0.3790.1830); Sun, 29 Jul 2007 21:56:41 -0400
X-MimeOLE: Produced By Microsoft Exchange V6.5
Content-class: urn:content-classes:message
MIME-Version: 1.0
Content-Type: text/plain; charset="US-ASCII"
Content-Transfer-Encoding: quoted-printable
Date: Sun, 29 Jul 2007 21:56:41 -0400
Message-ID: <F222151D3323874393F83102D614E0550A4D23F1@CORPUSMX20A.corp.emc.com>
X-MS-Has-Attach:
X-MS-TNEF-Correlator:
Thread-Topic: RFC 4963 on IPv4 Reassembly Errors at High Data Rates
Thread-Index: AcfQlkKAOYsucDDXTfuMfwhD+mCT4ABtMp+A
To: ips@ietf.org
X-OriginalArrivalTime: 30 Jul 2007 01:56:41.0781 (UTC) FILETIME=[DFD27E50:01C7D24C]
X-PMX-Version: 4.7.1.128075, Antispam-Engine: 2.5.1.298604, Antispam-Data: 2007.7.6.21134
X-PerlMx-Spam: Gauge=, SPAM=0%, Reason='EMC_BODY_1+ -3, EMC_FROM_0+ -3, NO_REAL_NAME 0, __C230066_P5 0, __CP_URI_IN_BODY 0, __CT 0, __CTE 0, __CT_TEXT_PLAIN 0, __HAS_MSGID 0, __IMS_MSGID 0, __MIME_TEXT_ONLY 0, __MIME_VERSION 0, __SANE_MSGID 0'
X-Spam-Score: -3.4 (---)
X-Scan-Signature: 8de5f93cb2b4e3bee75302e9eacc33db
Subject: [Ips] FW: RFC 4963 on IPv4 Reassembly Errors at High Data Rates
X-BeenThere: ips@ietf.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: IP Storage <ips.ietf.org>
List-Unsubscribe: <https://www1.ietf.org/mailman/listinfo/ips>, <mailto:ips-request@ietf.org?subject=unsubscribe>
List-Post: <mailto:ips@ietf.org>
List-Help: <mailto:ips-request@ietf.org?subject=help>
List-Subscribe: <https://www1.ietf.org/mailman/listinfo/ips>, <mailto:ips-request@ietf.org?subject=subscribe>
Errors-To: ips-bounces@ietf.org

FYI - IPv4 fragmentation can be harmful at high speed.  The
best bet is to not to allow fragmentation, but the RFC says:
"stronger error checking at any level above IP" is a mitigation
measure.  iSCSI digests and the end-to-end use of the FC frame
CRC by FCIP and iFCP are examples of this sort of "stronger
error checking".

--David
----------------------------------------------------
David L. Black, Senior Technologist
EMC Corporation, 176 South St., Hopkinton, MA  01748
+1 (508) 293-7953             FAX: +1 (508) 293-7786
black_david@emc.com        Mobile: +1 (978) 394-7754
----------------------------------------------------

-----Original Message-----
From: rfc-editor@rfc-editor.org [mailto:rfc-editor@rfc-editor.org] 
Sent: Friday, July 27, 2007 5:34 PM
To: ietf-announce@ietf.org; rfc-dist@rfc-editor.org
Cc: rfc-editor@rfc-editor.org
Subject: RFC 4963 on IPv4 Reassembly Errors at High Data Rates


A new Request for Comments is now available in online RFC libraries.

        
        RFC 4963

        Title:      IPv4 Reassembly Errors at High 
                    Data Rates 
        Author:     J. Heffner, M. Mathis,
                    B. Chandler
        Status:     Informational
        Date:       July 2007
        Mailbox:    jheffner@psc.edu, 
                    mathis@psc.edu, 
                    bchandle@gmail.com
        Pages:      10
        Characters: 22399
        Updates/Obsoletes/SeeAlso:   None

        I-D Tag:    draft-heffner-frag-harmful-05.txt

        URL:        http://www.rfc-editor.org/rfc/rfc4963.txt

IPv4 fragmentation is not sufficiently robust for use under some
conditions in today's Internet.  At high data rates, the 16-bit IP
identification field is not large enough to prevent frequent
incorrectly assembled IP fragments, and the TCP and UDP checksums are
insufficient to prevent the resulting corrupted datagrams from being
delivered to higher protocol layers.  This note describes some easily
reproduced experiments demonstrating the problem, and discusses some
of the operational implications of these observations.  This memo
provides information for the Internet community.


INFORMATIONAL: This memo provides information for the Internet
community. 
It does not specify an Internet standard of any kind. Distribution
of this memo is unlimited.

This announcement is sent to the IETF list and the RFC-DIST list.
Requests to be added to or deleted from the IETF distribution list
should be sent to IETF-REQUEST@IETF.ORG.  Requests to be
added to or deleted from the RFC-DIST distribution list should
be sent to RFC-DIST-REQUEST@RFC-EDITOR.ORG.

Details on obtaining RFCs via FTP or EMAIL may be obtained by sending
an EMAIL message to rfc-info@RFC-EDITOR.ORG with the message body 

help: ways_to_get_rfcs. For example:

        To: rfc-info@RFC-EDITOR.ORG
        Subject: getting rfcs

        help: ways_to_get_rfcs

Requests for special distribution should be addressed to either the
author of the RFC in question, or to RFC-Manager@RFC-EDITOR.ORG.  Unless
specifically noted otherwise on the RFC itself, all RFCs are for
unlimited distribution.

Submissions for Requests for Comments should be sent to
RFC-EDITOR@RFC-EDITOR.ORG.  Please consult RFC 2223, Instructions to RFC
Authors, for further information.


The RFC Editor Team
USC/Information Sciences Institute

...


_______________________________________________
IETF-Announce mailing list
IETF-Announce@ietf.org
https://www1.ietf.org/mailman/listinfo/ietf-announce


_______________________________________________
Ips mailing list
Ips@ietf.org
https://www1.ietf.org/mailman/listinfo/ips