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Delta encoding in HTTP

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 3229.
Authors Arthur van Hoff , Fred Douglis , Balachander Krishnamurthy , Yaron Y. Goland , Daniel M. Hellerstein , Anja Feldmann , Jeffrey Mogul
Last updated 2013-03-02 (Latest revision 2001-10-04)
RFC stream Legacy stream
Intended RFC status Proposed Standard
Stream Legacy state (None)
Consensus boilerplate Unknown
RFC Editor Note (None)
IESG IESG state Became RFC 3229 (Proposed Standard)
Action Holders
Telechat date (None)
Responsible AD Ned Freed
IESG note
Send notices to (None)
A new Request for Comments is now available in online RFC libraries.

        RFC 3229

        Title:      Delta encoding in HTTP
        Author(s):  J. Mogul, B. Krishnamurthy, F. Douglis,
                    A. Feldmann, Y. Goland, A. van Hoff,
                    D. Hellerstein 
        Status:     Standards Track
        Date:       January 2002
        Pages:      49
        Characters: 111953
        Updates/Obsoletes/SeeAlso:  None

        I-D Tag:    draft-mogul-http-delta-10.txt


This document describes how delta encoding can be supported as a
compatible extension to HTTP/1.1.

Many HTTP (Hypertext Transport Protocol) requests cause the retrieval
of slightly modified instances of resources for which the client
already has a cache entry.  Research has shown that such modifying
updates are frequent, and that the modifications are typically much
smaller than the actual entity.  In such cases, HTTP would make more
efficient use of network bandwidth if it could transfer a minimal
description of the changes, rather than the entire new instance of the
resource.  This is called "delta encoding."

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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