--- 1/draft-ietf-tcpm-urgent-data-05.txt 2010-08-23 22:15:36.000000000 +0200 +++ 2/draft-ietf-tcpm-urgent-data-06.txt 2010-08-23 22:15:36.000000000 +0200 @@ -1,57 +1,52 @@ TCP Maintenance and Minor F. Gont Extensions (tcpm) UTN/FRH Internet-Draft A. Yourtchenko Updates: 793, 1011, 1122 Cisco -(if approved) March 4, 2010 +(if approved) August 23, 2010 Intended status: Standards Track -Expires: September 5, 2010 +Expires: February 24, 2011 On the implementation of the TCP urgent mechanism - draft-ietf-tcpm-urgent-data-05.txt + draft-ietf-tcpm-urgent-data-06.txt Abstract This document analyzes how current TCP implementations process TCP urgent indications, and how the behavior of some widely-deployed middle-boxes affect how urgent indications are processed by end systems. This document updates the relevant specifications such that they accommodate current practice in processing TCP urgent indications, provides advice to applications that make use of the urgent mechanism, and raises awareness about the reliability of TCP urgent indications in the current Internet. Status of this Memo This Internet-Draft is submitted to IETF in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering - Task Force (IETF), its areas, and its working groups. Note that - other groups may also distribute working documents as Internet- - Drafts. + Task Force (IETF). Note that other groups may also distribute + working documents as Internet-Drafts. The list of current Internet- + Drafts is at http://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six months and may be updated, replaced, or obsoleted by other documents at any time. It is inappropriate to use Internet-Drafts as reference material or to cite them other than as "work in progress." - The list of current Internet-Drafts can be accessed at - http://www.ietf.org/ietf/1id-abstracts.txt. - - The list of Internet-Draft Shadow Directories can be accessed at - http://www.ietf.org/shadow.html. - - This Internet-Draft will expire on September 5, 2010. + This Internet-Draft will expire on February 24, 2011. Copyright Notice + Copyright (c) 2010 IETF Trust and the persons identified as the document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of @@ -49,21 +44,21 @@ document authors. All rights reserved. This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as - described in the BSD License. + described in the Simplified BSD License. Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 4 2. Specification of the TCP urgent mechanism . . . . . . . . . . 4 2.1. Semantics of urgent indications . . . . . . . . . . . . . 4 2.2. Semantics of the Urgent Pointer . . . . . . . . . . . . . 5 2.3. Allowed length of urgent data . . . . . . . . . . . . . . 5 3. Current implementation practice of TCP urgent data . . . . . . 5 3.1. Semantics of urgent indications . . . . . . . . . . . . . 5 @@ -86,26 +81,27 @@ A.2. Linux . . . . . . . . . . . . . . . . . . . . . . . . . . 10 A.3. NetBSD . . . . . . . . . . . . . . . . . . . . . . . . . . 10 A.4. OpenBSD . . . . . . . . . . . . . . . . . . . . . . . . . 11 A.5. Cisco IOS software . . . . . . . . . . . . . . . . . . . . 11 A.6. Microsoft Windows 2000, Service Pack 4 . . . . . . . . . . 11 A.7. Microsoft Windows 2008 . . . . . . . . . . . . . . . . . . 11 A.8. Microsoft Windows 95 . . . . . . . . . . . . . . . . . . . 12 Appendix B. Changes from previous versions of the draft (to be removed by the RFC Editor before publishing this document as an RFC) . . . . . . . . . . . . . . 12 - B.1. Changes from draft-ietf-tcpm-urgent-data-04 . . . . . . . 12 - B.2. Changes from draft-ietf-tcpm-urgent-data-03 . . . . . . . 12 - B.3. Changes from draft-ietf-tcpm-urgent-data-02 . . . . . . . 12 - B.4. Changes from draft-ietf-tcpm-urgent-data-01 . . . . . . . 12 - B.5. Changes from draft-ietf-tcpm-urgent-data-00 . . . . . . . 12 - B.6. Changes from draft-gont-tcpm-urgent-data-01 . . . . . . . 13 + B.1. Changes from draft-ietf-tcpm-urgent-data-05 . . . . . . . 12 + B.2. Changes from draft-ietf-tcpm-urgent-data-04 . . . . . . . 12 + B.3. Changes from draft-ietf-tcpm-urgent-data-03 . . . . . . . 12 + B.4. Changes from draft-ietf-tcpm-urgent-data-02 . . . . . . . 12 + B.5. Changes from draft-ietf-tcpm-urgent-data-01 . . . . . . . 12 + B.6. Changes from draft-ietf-tcpm-urgent-data-00 . . . . . . . 12 + B.7. Changes from draft-gont-tcpm-urgent-data-01 . . . . . . . 13 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 13 1. Introduction This document analyzes how some current TCP implementations process TCP urgent indications, and how the behavior of some widely-deployed middle-boxes affect the processing of urgent indications by hosts. This document updates RFC 793 [RFC0793], RFC 1011 [RFC1011], and RFC 1122 [RFC1122] such that they accommodate current practice in processing TCP urgent indications, provides advice to applications @@ -480,50 +476,55 @@ BSDUrgent system-wide variable to override this behavior, interpreting the Urgent Pointer as specified in RFC 1122 [RFC1122]. Windows 95 supports only one byte of urgent data. That is, only the byte preceding the Urgent Pointer is considered as "urgent data". [Windows95] Appendix B. Changes from previous versions of the draft (to be removed by the RFC Editor before publishing this document as an RFC) -B.1. Changes from draft-ietf-tcpm-urgent-data-04 +B.1. Changes from draft-ietf-tcpm-urgent-data-05 + + o Draft resubmitted (with no changes) because it was close to the + expiration day. + +B.2. Changes from draft-ietf-tcpm-urgent-data-04 o Fixes grammar errors wrt the term "data" (thanks to David Borman, once again ;-) ) -B.2. Changes from draft-ietf-tcpm-urgent-data-03 +B.3. Changes from draft-ietf-tcpm-urgent-data-03 o Addresses feedback sent by David Borman, and nit pointed out by John Heffner. -B.3. Changes from draft-ietf-tcpm-urgent-data-02 +B.4. Changes from draft-ietf-tcpm-urgent-data-02 o Addresses WGLC feedback submitted by Michael Welzl, Anantha Ramaiah, and Wesley Eddy. -B.4. Changes from draft-ietf-tcpm-urgent-data-01 +B.5. Changes from draft-ietf-tcpm-urgent-data-01 o Fixes reference to Cisco IOS Software (layer 8+ stuff ;-) ). o Cleaned-up Appendix A.5. -B.5. Changes from draft-ietf-tcpm-urgent-data-00 +B.6. Changes from draft-ietf-tcpm-urgent-data-00 o Minor editorial changes. o Incorporated the specific changes/advice stated in http://www.ietf.org/mail-archive/web/tcpm/current/msg04548.html in different sections (Section 4, Section 5, Section 6). -B.6. Changes from draft-gont-tcpm-urgent-data-01 +B.7. Changes from draft-gont-tcpm-urgent-data-01 o Draft resubmitted as draft-ietf, as a result of wg consensus on adopting the document as a tcpm wg item. Authors' Addresses Fernando Gont Universidad Tecnologica Nacional / Facultad Regional Haedo Evaristo Carriego 2644 Haedo, Provincia de Buenos Aires 1706