TCP Implementation (tcpimpl) ---------------------------- Charter Last Modified: 10/06/2000 Current Status: Concluded Working Group Chair(s): Vern Paxson Mark Allman Transport Area Director(s): Scott Bradner Allison Mankin Transport Area Advisor: Scott Bradner Mailing Lists: General Discussion:tcp-impl@grc.nasa.gov To Subscribe: majordomo@grc.nasa.gov Archive: http://tcp-impl.grc.nasa.gov/tcp-impl Description of Working Group: The objective of this group is to decide how to best address known problems in existing implementations of the current TCP standard(s) and practices. The overall goal is to improve conditions in the existing Internet by enhancing the quality of current TCP/IP implementations. It is hoped that both performance and correctness issues can be resolved by making implementors aware of the problems and their solutions. In the long term, it is felt that this will provide a reduction in unnecessary traffic on the network, the rate of connection failures due to protocol errors, and load on network servers due to time spent processing both unsuccessful connections and retransmitted data. This will help to ensure the stability of the global Internet. Examples of detected problems: o TCPs that retransmit all unacknowledged data at a single time. This behavior greatly adds to Internet load, at a time when the network is already under stress. The combination can lead to congestion collapse. o TCPs that misinitialize the congestion window, leading to potentially enormous bursts of traffic when new connections begin. Such burstiness can greatly stress Internet routers. In the BOF, it was generally agreed that problems of this class need to be fixed. Scope: The scope of this group must be carefully defined in order to ensure timely progress. To this end, TCP issues that still remain areas of research are considered out of scope for the WG. For example new improvements in congestion control algorithms are not within the WG scope. The WG will solicit input from the End-To-End research group of the IRTF on questions of whether a TCP implementation issue is considered research. The major objectives of this group will be to : Produce a compilation of known problems and their solutions. This will raise awareness of these issues. Determine if any problems found are the result of ambiguities in the TCP specification. If necessary, produce a document which clarifies the specification. Catalog existing TCP test suites, diagnostic tools, testing organizations, and procedures that can be used by implementors to improve their code, and produce a document enumerating them. Goals and Milestones: Done Working group formation. Decide on document editors. Done Define schedule for producing the test suite catalog Done First Internet-Draft of problems and fixes, and very rough first draft of catalogue of test suites. Done Issue revised Internet-Draft documents. Done Cut-off for determining whether clarification document is needed. If necessary, have interim meeting to focus effort on clarification document. Done Submit Internet-Draft of test catalogue to IESG for publication as an RFC. Done Submit Internet-Draft of problems and fixes to IESG for publication as an RFC. Done Submit Internet-Draft clarifying RFCs 793, 1122, and 1323 to IESG for publication as an RFC. Done Submit Internet-Draft on increasing TCP's initial window size for publication as an experimental RFC. Done Submit Internet-Draft of test catalogue to IESG for consideration as an informational RFC. Done Submit I-Ds in support of larger initial window I-D to IESG for consideration as an Informational RFCs Done Begin work on revisions to RFC 2001. Done Begin work on a security problems document (to be much like the known problems I-D currently being developed). Done Submit revised version of problems and fixes as an Internet-Draft. Done Submit problems and fixes document to IESG for consideration as an Informational RFC. Done Submit revision of RFC 2001 to IESG for publication as Proposed Standard. Most likely this will include changes to the initial window, reflecting experienced gained with the Experimental initial window RFC. May include changes to restart-after-idle behavior Done submit Internet-Draft on problems with Path MTU discovery to IESG for publication as an Informational RFC Done Conclude Working Group Internet-Drafts: No Current Internet-Drafts. Request For Comments: RFC Stat Published Title ------- -- ----------- ------------------------------------ RFC2398 I AUG 98 Some Testing Tools for TCP Implementors RFC2414 E SEP 98 Increasing TCP's Initial Window RFC2415 I SEP 98 Simulation Studies of Increased Initial TCP Window Size RFC2416 I SEP 98 When TCP Starts Up With Four Packets Into Only Three Buffers RFC2525 I MAR 99 Known TCP Implementation Problems RFC2582 E APR 99 The NewReno Modification to TCP's Fast Recovery Algorithm RFC2581 PS APR 99 TCP Congestion Control RFC2923 I SEP 00 TCP Problems with Path MTU Discovery