Subject: Protocol Action: Enhancing TCP's Loss Recovery Using Limited Transmit to Proposed Standard

From: The IESG <[email-masked]>
Date: Fri, 24 Nov 2000 17:29:05 -0500

The IESG has approved the Internet-Draft 'Enhancing TCP's Loss Recovery
Using Limited Transmit' <draft-ietf-tsvwg-limited-xmit-00.txt> as a
Proposed Standard.  This document is the product of the Transport Area
Working Group Working Group.  The IESG contact persons are Allison
Mankin and Scott Bradner.

Technical Summary
 
    This document proposes a new TCP mechanism that can be used to more
    effectively recover lost segments when a connection's congestion
    window is small, or when a large number of segments are lost in a
    single transmission window.  The ``Limited Transmit'' algorithm
    calls for sending a new data segment in response to each of the
    first two duplicate acknowledgments that arrive at the sender.
    Transmitting these segments increases the probability that TCP can
    recover from a single lost segment using the fast retransmit
    algorithm, rather than using a costly retransmission timeout.
    Limited Transmit can be used both in conjunction with, and in the
    absence of, the TCP selective acknowledgment (SACK) mechanism
    [RFC2018].

Working Group Summary

  The working group supported the advancement of this spec, with
  a strong degree of consensus, while judging a companion algorithm
  to this, called Early Fast Retransmit, to be less ready for
  standardization.

Protocol Quality

  The spec was reviewed for the IESG by Allison Mankin.
  Implementations are encouraged.

RFC Editor Notes

  1. Please make the following clarification change that
     was identified and confirmed during Last Call.

     Change -
      * The amount of outstanding data would remain less than the
        congestion window plus 2 segments.
     To -
      * The amount of outstanding data would remain less than or
        equal to the congestion window plus 2 segments.

  2. As requested by IANA, please delete the reference to
     [DMKM00] draft-ietf-pilc-slow-03.txt.

  3. Please add the appended text to the end of Section 1 of
     draft-ietf-tsvwg-limited-xmit-00.txt (that is, as a new section 
     following the sentence "These changes do not adversely affect the 
     performance of TCP nor interact adversely with other connections,
     in other circumstances."
 
	1.1  Terminology

	In this document, the key words "MUST", "MUST NOT",
	"REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "SHOULD
	NOT", "RECOMMENDED", "MAY", and "OPTIONAL" are to be
        interpreted as described in RFC 2119 [1] and indicate
        requirement levels for the protocol.

  4. Please add a reference to RFC 2119 to the References section.