TCP Maintenance and Minor Extensions (tcpm)
-------------------------------------------

 Charter
 Last Modified: 2010-03-09

 Current Status: Active Working Group

 Chair(s):
     Wesley Eddy  <weddy@grc.nasa.gov>
     David Borman  <david.borman@windriver.com>

 Transport Area Director(s):
     David Harrington  <ietfdbh@comcast.net>
     Lars Eggert  <lars.eggert@nokia.com>

 Transport Area Advisor:
     Lars Eggert  <lars.eggert@nokia.com>

 Mailing Lists: 
     General Discussion:tcpm@ietf.org
     To Subscribe:      https://www.ietf.org/mailman/listinfo/tcpm
     Archive:           http://www.ietf.org/mail-archive/web/tcpm/index.html

Description of Working Group:

TCP is currently the Internet's predominant transport protocol. 
To maintain TCP's utility the IETF has regularly updated both 
the protocol itself and the congestion control algorithms 
implemented by the protocol that are crucial for the stability 
of the Internet. These changes reflect our evolving 
understanding of transport protocols, congestion control and new 
needs presented by an ever-changing network. The TCPM WG will 
provide a venue within the IETF to work on these issues. The WG 
will serve several purposes: 

* The WG will mostly focus on maintenance issues (e.g., bug 
fixes) and modest changes to the protocol and algorithms 
that maintain TCP's utility. 

* The WG will be a venue for moving current TCP specifications 
along the standards track (as community energy is available 
for such efforts). 

* The WG will write a document that outlines "what is TCP". 
This document will be a roadmap of sorts to the various TCP 
specifications in the RFC series. 

TCPM will take a subset of the work which has been conducted in 
the Transport Area WG over the past several years. 
Specifically, some of the WG's initial work will be moved from 
the Transport Area WG (tsvwg). 

TCPM is expected to be the working group within the IETF to 
handle TCP changes. Proposals for additional TCP work items 
should be brought up within the working group. While 
fundamental changes to TCP or its congestion control algorithms 
(e.g., departure from loss-based congestion control) should be 
brought through TCPM, it is expected that such large changes 
will ultimately be handled by the Transport Area WG (tsvwg). 
All additional work items for TCPM will, naturally, require the 
approval of the Transport Services Area Area Directors and the 
IESG. 

TCP's congestion control algorithms are the model followed by 
alternate transports (e.g., SCTP and (in some cases) DCCP). In 
addition, the IETF has recently worked on several documents 
about algorithms that are specified for multiple protocols 
(e.g., TCP and SCTP) in the same document. Which WG shepherds 
such documents in the future will determined on a case-by-case 
basis. In any case, the TCPM WG will remain in close contact 
with other relevant WGs working on these protocols to ensure 
openness and stringent review from all angles. 

Specific Goals: 

* A document specifying a way to share the local "User TimeOut" 
value with the peer such that TCP connections can withstand long 
periods of disconnection. 
 
* The WG is coming to grips with how to deal with spoofed segments 
that can tear down connections, cause data corruption or 
performance problems. To this end the WG is generating an 
overview document as well as a scheme that mitigates some of the 
issues brought on by spoofed TCP segments using a 
challenge-response scheme to reduce the probabilities of a 
connection being impacted. Finally, the WG will produce a 
document outlining the potential impact of using ICMP messages 
to attack TCP streams. 
 
* The WG is writing an informational document about the ways in 
which TCPs can handle ICMP "soft errors". 
 
* The WG is updating the specification for Explicit Congestion 
Notification to allow for the use of ECN during part of TCP's 
three-way handshake to aid performance for short transfers. 
 
* The WG is writing an informational document that discusses 
commonly used, but not documented ways to combat SYN flooding 
attacks. 
 
* The WG is updating RFC 2581 to fix some minor specification 
problems and move it along the standards track.

 Goals and Milestones:

   Done         Submit FRTO draft to IESG for publication as an Experimental 
                RFC 

   Done         Submit TCP Roadmap document to IESG for publication as a Best 
                Current Practices RFC 

   Done         Submit NCR Reordering Mitigation draft to the IESG for 
                publication as an Experimental RFC 

   Done         Submit overview of spoofing attacks against TCP to IESG for 
                publication as an Informational RFC 

   Done         Submit User TimeOut option document to the IESG for publication 
                as a Proposed Standard RFC 

   Done         Submit SYN flooding document to the IESG for publication as an 
                Informational RFC 

   Done         Submit soft errors document to the IESG for publication as an 
                Informational RFC 

   Done         Submit ECN-SYN document to the IESG for publication as a 
                Proposed Standard RFC 

   Done         Submit revision of RFC 2581 to the IESG for publication as a 
                Draft Standard 

   Done         Submit In-Window Attack draft to IESG for publication as a 
                Proposed Standard RFC 

   Done         Submit TCP Authentication Option document to the IESG for 
                Proposed Standard RFC 

   Jul 2009       Submit update to RFC 1323 to the IESG for Proposed Standard RFC 

   Jul 2009       Submit MSS text revision originally from RFC 1323 appendix to 
                the IESG for Proposed Standard RFC 

   Done         Submit ICMP attack document to the IESG for publication as an 
                Informational RFC 

   Done         Submit TCP Early-Retransmit document to the IESG for 
                Experimental RFC 

   Jan 2010       Submit TCP Urgent Pointer draft to IESG for publication as a 
                Proposed Standard RFC 

   Aug 2010       Submit document on security hardening of TCP implementations to 
                the IESG for publication as a Best Current Practices RFC 

   Oct 2010       Submit document on the use of SACK data to trigger loss 
                recovery to the IESG for Proposed Standard 

   Oct 2010       Submit document on mitigation of 'Long Connectivity 
                Disruptions' to the IESG for Experimental 


 Internet-Drafts:

Posted Revised         I-D Title   <Filename>
------ ------- --------------------------------------------
Apr 2004 May 2010   <draft-ietf-tcpm-tcpsecure-13.txt>
                Improving TCP's Robustness to Blind In-Window Attacks 

Feb 2006 Mar 2010   <draft-ietf-tcpm-icmp-attacks-12.txt>
                ICMP attacks against TCP 

Nov 2007 Mar 2010   <draft-ietf-tcpm-tcp-auth-opt-11.txt>
                The TCP Authentication Option 

Mar 2009 Mar 2010   <draft-ietf-tcpm-tcpmss-03.txt>
                This memo discusses what value to use with the TCP MSS option. 

May 2009 Mar 2010   <draft-ietf-tcpm-urgent-data-05.txt>
                On the implementation of the TCP urgent mechanism 

Aug 2009 Feb 2010   <draft-ietf-tcpm-tcp-security-01.txt>
                Security Assessment of the Transmission Control Protocol (TCP) 

Sep 2009 Mar 2010   <draft-ietf-tcpm-tcp-ao-crypto-03.txt>
                Cryptographic Algorithms for TCP's Authentication Option, 
                TCP-AO 

Oct 2009 Mar 2010   <draft-ietf-tcpm-sack-recovery-entry-01.txt>
                Using TCP Selective Acknowledgement (SACK) Information to 
                Determine Duplicate Acknowledgements for Loss Recovery 
                Initiation 

Nov 2009 Mar 2010   <draft-ietf-tcpm-tcp-lcd-01.txt>
                Making TCP more Robust to Long Connectivity Disruptions 
                (TCP-LCD) 

 Request For Comments:

  RFC   Stat Published     Title
------- -- ----------- ------------------------------------
RFC4138 E    Aug 2005    Forward RTO-Recovery (F-RTO): An Algorithm for Detecting 
                       Spurious Retransmission Timeouts with TCP and the Stream 
                       Control Transmission Protocol (SCTP) 

RFC4653 E    Aug 2006    Improving the Robustness of TCP to Non-Congestion Events 

RFC4614 I    Sep 2006    A Roadmap for Transmission Control Protocol (TCP) 
                       Specification Documents 

RFC4953 I    Jul 2007    Defending TCP Against Spoofing Attacks 

RFC4987 I    Aug 2007    TCP SYN Flooding Attacks and Common Mitigations 

RFC5461 I    Feb 2009    TCP's Reaction to Soft Errors 

RFC5482 PS   Mar 2009    TCP User Timeout Option 

RFC5562 E    Jun 2009    Adding Explicit Congestion Notification (ECN) Capability 
                       to TCP's SYN/ACK Packets 

RFC5681 DS   Sep 2009    TCP Congestion Control 

RFC5682 PS   Sep 2009    Forward RTO-Recovery (F-RTO): An Algorithm for Detecting 
                       Spurious Retransmission Timeouts with TCP 

RFC5827 E    Apr 2010    Early Retransmit for TCP and Stream Control Transmission 
                       Protocol (SCTP)