A new Request for Comments is now available in online RFC libraries.

        RFC 3230

        Title:      Instance Digests in HTTP
        Author(s):  J. Mogul, A. Van Hoff
        Status:     Standards Track
        Date:       January 2002
        Mailbox:    JeffMogul@acm.org, avh@marimba.com
        Pages:      13
        Characters: 26846
        Updates/Obsoletes/SeeAlso:  None

        I-D Tag:    draft-mogul-http-digest-05.txt

        URL:        ftp://ftp.rfc-editor.org/in-notes/rfc3230.txt

HTTP/1.1 defines a Content-MD5 header that allows a server to include
a digest of the response body.  However, this is specifically defined
to cover the body of the actual message, not the contents of the full
file (which might be quite different, if the response is a
Content-Range, or uses a delta encoding).  Also, the Content-MD5 is
limited to one specific digest algorithm; other algorithms, such as
SHA-1 (Secure Hash Standard), may be more appropriate in some
circumstances.  Finally, HTTP/1.1 provides no explicit mechanism by
which a client may request a digest.  This document proposes HTTP
extensions that solve these problems.

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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