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A Conservative Selective Acknowledgment (SACK)-based Loss Recovery Algorithm for TCP

The information below is for an old version of the document that is already published as an RFC.
Document Type
This is an older version of an Internet-Draft that was ultimately published as RFC 3517.
Authors Mark Allman , Ethan Blanton , Kevin Fall
Last updated 2013-03-02 (Latest revision 2002-10-09)
RFC stream Internet Engineering Task Force (IETF)
Additional resources Mailing list discussion
Stream WG state (None)
Document shepherd (None)
IESG IESG state RFC 3517 (Proposed Standard)
Consensus boilerplate Unknown
Telechat date (None)
Responsible AD Scott O. Bradner
Send notices to <>, <>
A new Request for Comments is now available in online RFC libraries.

        RFC 3517

        Title:      A Conservative Selective Acknowledgment
                    (SACK)-based Loss Recovery Algorithm for TCP
        Author(s):  E. Blanton, M. Allman, K. Fall, L. Wang
        Status:     Standards Track
        Date:       April 2003
        Pages:      13
        Characters: 27855
        Updates/Obsoletes/SeeAlso:  None

        I-D Tag:    draft-allman-tcp-sack-13.txt


This document presents a conservative loss recovery algorithm
for TCP that is based on the use of the selective acknowledgment
(SACK) TCP option.  The algorithm presented in this document conforms
to the spirit of the current congestion control specification
(RFC 2581), but allows TCP senders to recover more effectively
when multiple segments are lost from a single flight of data.

This document is a product of the Transport Area Working Group of the

This is now a Proposed Standard Protocol.

This document specifies an Internet standards track protocol for
the Internet community, and requests discussion and suggestions
for improvements.  Please refer to the current edition of the
"Internet Official Protocol Standards" (STD 1) for the
standardization state and status of this protocol.  Distribution
of this memo is unlimited.

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