RFC 1544 (rfc1544) - Page 1 of 3
The Content-MD5 Header Field
Alternative Format: Original Text Document
Network Working Group M. Rose
Request for Comments: 1544 Dover Beach Consulting, Inc.
Category: Standards Track November 1993
The Content-MD5 Header Field
Status of this Memo
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.
Abstract
This memo specifies an optional header field, Content-MD5, for use
with MIME-conformant messages.
Table of Contents
1. Introduction .......................................... 1
2. Generation of the Content-MD5 Field ................... 2
3. Processing the Content-MD5 field ...................... 2
4. Security Considerations ............................... 3
5. Acknowledgements ...................................... 3
6. References ............................................ 3
7. Author's Address ...................................... 3
1. Introduction
Despite all of the mechanisms provided by MIME [1] which attempt to
protect data from being damaged in the course of email transport, it
is still desirable to have a mechanism for verifying that the data,
once decoded, are intact. For this reason, this memo defines the use
of an optional header field, Content-MD5, which may be used as a
message integrity check (MIC), to verify that the decoded data are
the same data that were initially sent.
MD5 is an algorithm for computing a 128 bit "digest" of arbitrary-
length data, with a high degree of confidence that any alterations in
the data will be reflected in alterations in the digest. The MD5
algorithm itself is defined in [2]. This memo specifies how the
algorithm may be used as an integrity check for MIME mail.
Rose
