The MIME Multipart/Related Content-type
RFC 2387
Document | Type |
RFC - Proposed Standard
(August 1998; Errata)
Obsoletes RFC 2112
|
|
---|---|---|---|
Author | Ed Levinson | ||
Last updated | 2020-05-06 | ||
Stream | IETF | ||
Formats | plain text html pdf htmlized with errata bibtex | ||
Stream | WG state | (None) | |
Document shepherd | No shepherd assigned | ||
IESG | IESG state | RFC 2387 (Proposed Standard) | |
Consensus Boilerplate | Unknown | ||
Telechat date | |||
Responsible AD | (None) | ||
Send notices to | (None) |
Network Working Group E. Levinson Request for Comments: 2387 August 1998 Obsoletes: 2112 Category: Standards Track The MIME Multipart/Related Content-type 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. Copyright Notice Copyright (C) The Internet Society (1998). All Rights Reserved. Abstract The Multipart/Related content-type provides a common mechanism for representing objects that are aggregates of related MIME body parts. This document defines the Multipart/Related content-type and provides examples of its use. 1. Introduction Several applications of MIME, including MIME-PEM, and MIME-Macintosh and other proposals, require multiple body parts that make sense only in the aggregate. The present approach to these compound objects has been to define specific multipart subtypes for each new object. In keeping with the MIME philosophy of having one mechanism to achieve the same goal for different purposes, this document describes a single mechanism for such aggregate or compound objects. The Multipart/Related content-type addresses the MIME representation of compound objects. The object is categorized by a "type" parameter. Additional parameters are provided to indicate a specific starting body part or root and auxiliary information which may be required when unpacking or processing the object. Multipart/Related MIME entities may contain Content-Disposition headers that provide suggestions for the storage and display of a body part. Multipart/Related processing takes precedence over Content-Disposition; the interaction between them is discussed in section 4. Levinson Standards Track [Page 1] RFC 2387 Multipart/Related August 1998 Responsibility for the display or processing of a Multipart/Related's constituent entities rests with the application that handles the compound object. 2. Multipart/Related Registration Information The following form is copied from RFC 1590, Appendix A. To: IANA@isi.edu Subject: Registration of new Media Type content-type/subtype Media Type name: Multipart Media subtype name: Related Required parameters: Type, a media type/subtype. Optional parameters: Start Start-info Encoding considerations: Multipart content-types cannot have encodings. Security considerations: Depends solely on the referenced type. Published specification: RFC-REL (this document). Person & email address to contact for further information: Edward Levinson 47 Clive Street Metuchen, NJ 08840-1060 +1 908 494 1606 XIson@cnj.digex.net 3. Intended usage The Multipart/Related media type is intended for compound objects consisting of several inter-related body parts. For a Multipart/Related object, proper display cannot be achieved by individually displaying the constituent body parts. The content-type of the Multipart/Related object is specified by the type parameter. The "start" parameter, if given, points, via a content-ID, to the body part that contains the object root. The default root is the first body part within the Multipart/Related body. The relationships among the body parts of a compound object distinguishes it from other object types. These relationships are often represented by links internal to the object's components that Levinson Standards Track [Page 2] RFC 2387 Multipart/Related August 1998 reference the other components. Within a single operating environment the links are often file names, such links may be represented within a MIME message using content-IDs or the value of some other "Content-" headers. 3.1. The Type Parameter The type parameter must be specified and its value is the MIME media type of the "root" body part. It permits a MIME user agent to determine the content-type without reference to the enclosed body part. If the value of the type parameter and the root body part's content-type differ then the User Agent's behavior is undefined. 3.2. The Start Parameter The start parameter, if given, is the content-ID of the compound object's "root". If not present the "root" is the first body part inShow full document text