--- 1/draft-ietf-tcpm-ecnsyn-04.txt 2008-02-19 21:12:14.000000000 +0100 +++ 2/draft-ietf-tcpm-ecnsyn-05.txt 2008-02-19 21:12:14.000000000 +0100 @@ -1,22 +1,22 @@ Internet Engineering Task Force A. Kuzmanovic INTERNET-DRAFT A. Mondal Intended status: Proposed Standard Northwestern University -Expires: 8 July 2008 S. Floyd +Expires: 19 August 2008 S. Floyd ICIR K.K. Ramakrishnan AT&T - 8 January 2008 + 19 February 2008 Adding Explicit Congestion Notification (ECN) Capability to TCP's SYN/ACK Packets - draft-ietf-tcpm-ecnsyn-04.txt + draft-ietf-tcpm-ecnsyn-05.txt Status of this Memo By submitting this Internet-Draft, each author represents that any applicable patent or other IPR claims of which he or she is aware have been or will be disclosed, and any of which he or she becomes aware will be disclosed, in accordance with Section 6 of BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF), its areas, and its working groups. Note that @@ -27,25 +27,25 @@ 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 December 2007. + This Internet-Draft will expire on August 2008. Copyright Notice - Copyright (C) The IETF Trust (2007). + Copyright (C) The IETF Trust (2008). Abstract This draft specifies a modification to RFC 3168 to allow TCP SYN/ACK packets to be ECN-Capable. For TCP, RFC 3168 only specifies setting an ECN-Capable codepoint on data packets, and not on SYN and SYN/ACK packets. However, because of the high cost to the TCP transfer of having a SYN/ACK packet dropped, with the resulting retransmit timeout, this document specifies the use of ECN for the SYN/ACK packet itself, when sent in response to a SYN packet with the two ECN @@ -55,43 +55,47 @@ timeout for a connection that has not yet started placing a load on the network. The sender of the SYN/ACK packet must respond to a report of an ECN-marked SYN/ACK packet by reducing its initial congestion window from two, three, or four segments to one segment, thereby reducing the subsequent load from that connection on the network. This document is intended to update RFC 3168. Table of Contents 1. Introduction ....................................................4 - 2. Conventions and Terminology .....................................6 + 2. Conventions and Terminology .....................................5 3. Proposal ........................................................6 4. Discussion ......................................................9 5. Related Work ...................................................12 - 6. Performance Evaluation .........................................13 - 6.1. The Costs and Benefit of Adding ECN-Capability ............13 + 6. Performance Evaluation .........................................12 + 6.1. The Costs and Benefit of Adding ECN-Capability ............12 6.2. An Evaluation of Different Responses to ECN-Marked SYN/ACK Packets ........................................................14 - 7. Security Considerations ........................................15 + 7. Security Considerations ........................................14 8. Conclusions ....................................................16 - 9. Acknowledgements ...............................................17 + 9. Acknowledgements ...............................................16 A. Report on Simulations ..........................................17 A.1. Simulations with RED in Packet Mode .......................17 A.2. Simulations with RED in Byte Mode .........................19 B. Issues of Incremental Deployment ...............................20 Normative References ..............................................23 Informative References ............................................23 IANA Considerations ...............................................24 Full Copyright Statement ..........................................25 Intellectual Property .............................................25 NOTE TO RFC EDITOR: PLEASE DELETE THIS NOTE UPON PUBLICATION. + Changes from draft-ietf-tcpm-ecnsyn-04: + + * Updating the copyright date. + Changes from draft-ietf-tcpm-ecnsyn-03: * General editing. This includes using the terms "initiator" and "responder" for the two ends of the TCP connection. Feedback from Alfred Hoenes. * Added some text to the backwards compatibility discussion, now in Appendix B, about the pros and cons of using a TCP flag for the TCP initiator to signal that it understands ECN-Capable SYN/ACK packets. The consensus at this time is @@ -1103,21 +1107,21 @@ URL: http://www.icir.org/floyd/ K. K. Ramakrishnan Phone: +1 (973) 360-8764 AT&T Labs Research Email: kkrama at research.att.com URL: http://www.research.att.com/info/kkrama Full Copyright Statement - Copyright (C) The IETF Trust (2007). + Copyright (C) The IETF Trust (2008). This document is subject to the rights, licenses and restrictions contained in BCP 78, and except as set forth therein, the authors retain all their rights. This document and the information contained herein are provided on an "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY, THE IETF TRUST AND THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF