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
        Mailbox:    JeffMogul@acm.org, bala@research.att.com,
                    douglis@research.att.com, anja@cs.uni-sb.de,
                    yaron@goland.org, avh@marimba.com,
        Pages:      49
        Characters: 111953
        Updates/Obsoletes/SeeAlso:  None

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

        URL:        ftp://ftp.rfc-editor.org/in-notes/rfc3229.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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