RFC - 2046

Multipurpose Internet Mail Extensions (MIME) Part Two: Media Types

Original:	ftp://ftp.isi.edu/in-notes/rfc2046.txt
Authors:	N. Freed [Innosoft], N. Borenstein [First Virtual]
Date:	November 1996
Category:	Draft Standard

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Obsoletes:
RFC-1590	Media Type Registration Procedure (Obsoleted by RFC-2048 -> RFC-4288; -> RFC-4289, RFC-2049draft, RFC-2047draft, RFC-2045draft, RFC-2046draft)
RFC-1522	MIME (Multipurpose Internet Mail Extensions) Part Two: Message Header Extensions for Non-ASCII Text (Obsoleted by RFC-2048 -> RFC-4288; -> RFC-4289, RFC-2049draft, RFC-2047draft, RFC-2045draft, RFC-2046draft)
RFC-1521	MIME (Multipurpose Internet Mail Extensions) Part One: Mechanisms for Specifying and Describing the Format of Internet Message Bodies (Obsoleted by RFC-2048 -> RFC-4288; -> RFC-4289, RFC-2049draft, RFC-2047draft, RFC-2045draft, RFC-2046draft) (Updated by RFC-1590)

Updated by:
RFC-3798draft	Message Disposition Notification
RFC-2646	The Text/Plain Format Parameter (Obsoleted by RFC-3676prop)

Referred by:	124 RFC
Refers to:	17 RFC

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Status

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

STD 11, RFC 822^std11(-> 2822^prop) defines a message representation protocol specifying considerable detail about US-ASCII message headers, but which leaves the message content, or message body, as flat US-ASCII text. This set of documents, collectively called the Multipurpose Internet Mail Extensions, or MIME, redefines the format of messages to allow for

1. textual message bodies in character sets other than US-ASCII,
2. an extensible set of different formats for non-textual message bodies,
3. multi-part message bodies, and
4. textual header information in character sets other than US-ASCII.

These documents are based on earlier work documented in RFC 934, STD 11, and RFC 1049^hist, but extends and revises them. Because RFC 822^std11(-> 2822^prop) said so little about message bodies, these documents are largely orthogonal to (rather than a revision of) RFC 822^std11(-> 2822^prop).

The initial document in this set, RFC 2045^draft, specifies the various headers used to describe the structure of MIME messages. This second document defines the general structure of the MIME media typing system and defines an initial set of media types. The third document, RFC 2047^draft, describes extensions to RFC 822^std11(-> 2822^prop) to allow non-US-ASCII text data in Internet mail header fields. The fourth document, RFC 2048(-> 4289 | 4288), specifies various IANA registration procedures for MIME-related facilities. The fifth and final document, RFC 2049^draft, describes MIME conformance criteria as well as providing some illustrative examples of MIME message formats, acknowledgements, and the bibliography.

These documents are revisions of RFCs 1521(-> 2049^draft | 2048(-> 4289 | 4288) | 2047^draft | 2046^draft | 2045^draft) and 1522(-> 2049^draft | 2048(-> 4289 | 4288) | 2047^draft | 2046^draft | 2045^draft), which themselves were revisions of RFCs 1341(-> 1521(-> 2049^draft | 2048(-> 4289 | 4288) | 2047^draft | 2046^draft | 2045^draft)) and 1342(-> 1522(-> 2049^draft | 2048(-> 4289 | 4288) | 2047^draft | 2046^draft | 2045^draft)). An appendix in RFC 2049^draft describes differences and changes from previous versions.

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