draft-ietf-conneg-content-features-02.txt   rfc2912.txt 
IETF conneg working group Graham Klyne
Internet draft Content Technologies
Category: Work-in-progress 30 November 1999
Expires: May 2000
Indicating media features for MIME content
<draft-ietf-conneg-content-features-02.txt>
Status of this memo Network Working Group G. Klyne
Request for Comments: 2912 Content Technologies
This document is an Internet-Draft and is in full conformance with Category: Standards Track September 2000
all provisions of Section 10 of RFC 2026.
Internet-Drafts are working documents of the Internet Engineering
Task Force (IETF), its areas, and its working groups. Note that
other groups may also distribute working documents as Internet-
Drafts.
Internet-Drafts are draft documents valid for a maximum of six Indicating Media Features for MIME Content
months and may be updated, replaced, or obsoleted by other
documents at any time. It is inappropriate to use Internet- Drafts
as reference material or to cite them other than as "work in
progress."
The list of current Internet-Drafts can be accessed at Status of this Memo
http://www.ietf.org/ietf/1id-abstracts.txt
The list of Internet-Draft Shadow Directories can be accessed at This document specifies an Internet standards track protocol for the
http://www.ietf.org/shadow.html. 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 Notice
Copyright (C) The Internet Society 1999. All Rights Reserved. Copyright (C) The Internet Society (2000). All Rights Reserved.
Abstract Abstract
In "A syntax for describing media feature sets", an expression In "A Syntax for Describing Media Feature Sets", an expression format
format is presented for describing media feature capabilities using is presented for describing media feature capabilities using simple
simple media feature tags. media feature tags.
This memo defines a MIME 'Content-features:' header that can be
used to annotate a MIME message part using this expression format,
and indicates some ways it might be used.
Internet draft Indicating media features for MIME content This memo defines a Multipurpose Internet Mail Extensions (MIME)
30 November 1999 'Content-features:' header that can be used to annotate a MIME
message part using this expression format, and indicates some ways it
might be used.
Table of contents Table of Contents
1. Introduction ............................................2 1. Introduction ............................................... 2
1.1 Terminology and document conventions 3 1.1 Terminology and document conventions ................... 2
1.2 Discussion of this document 3 2. Motivation and goals ....................................... 3
2. Motivation and goals ....................................4 3. The 'Content-features:' MIME header ........................ 4
3. The 'Content-features:' MIME header .....................4 3.1 Whitespace and folding long headers .................... 4
3.1 Usage considerations 4 3.2 Usage considerations ................................... 4
3.1.1 Simple message parts 4 3.2.1 Simple message parts ............................... 4
3.1.2 Multipart and other composites 5 3.2.2 Multipart and other composites ..................... 5
3.1.3 Reference to external data 5 3.2.3 Reference to external data ......................... 5
4. Examples ................................................5 4. Examples ................................................... 5
4.1 Simple message 5 4.1 Simple message ......................................... 5
4.2 Fax message 6 4.2 Fax message ............................................ 6
4.3 Multipart/alternative data 6 4.3 Multipart/alternative data ............................. 6
4.4 Reference to external message data 7 4.4 Reference to external message data ..................... 8
4.5 Compressed data 8 4.5 Compressed data ........................................ 8
4.6 Multipart/related data 8 4.6 Multipart/related data ................................. 8
5. Security considerations .................................9 5. Security Considerations .................................... 9
6. Acknowledgements ........................................9 6. Acknowledgements ........................................... 10
7. References ..............................................9 7. References ................................................. 10
8. Author's address ........................................10 8. Author's Address ........................................... 10
Full copyright statement ...................................11 Full Copyright Statement ...................................... 11
Revision history ...........................................11
1. Introduction 1. Introduction
In "A syntax for describing media feature sets" [1], an expression In "A Syntax for Describing Media Feature Sets" [1], an expression
format is presented for describing media feature capabilities as a format is presented for describing media feature capabilities as a
combination of simple media feature tags, registered according to combination of simple media feature tags, registered according to
"Media Feature Tag Registration Procedure" [2]. This provides a "Media Feature Tag Registration Procedure" [2]. This provides a
format for message handling agents to describe the media feature format for message handling agents to describe the media feature
content of messages that they can handle. content of messages that they can handle.
This memo defines a MIME 'Content-features:' header that can be
used to annotate a MIME message part using these feature
expressions. This header provides a means to indicate media-
related features of message content that go beyond the MIME content
type.
Along with the new MIME header definition, consideration is also This memo defines a MIME 'Content-features:' header that can be used
given to how it may be used to present message media content to annotate a MIME message part using these feature expressions.
information that is problematic to express within the basic MIME This header provides a means to indicate media-related features of
framework. message content that go beyond the MIME content type.
Internet draft Indicating media features for MIME content Consideration is also given to how it may be used to present message
30 November 1999 media content information that is problematic to express within the
basic MIME framework.
1.1 Terminology and document conventions 1.1 Terminology and document conventions
This section defines a number of terms and other document This section defines a number of terms and other document
conventions, which are used with specific meaning in this memo. conventions, which are used with specific meaning in this memo.
media feature
information that indicates facilities assumed to be
available for the message content to be properly rendered
or otherwise presented. Media features are not intended
to include information that affects message transmission.
feature set
some set of media features described by a media feature
assertion, as described in "A syntax for describing media
feature sets" [1]. (See that memo for a more formal
definition of this term.)
feature set expression
a string that describes some feature set, formulated
according to the rules in "A syntax for describing media
feature sets" [1] (and possibly extended by other
specifications).
This specification uses syntax notation and conventions described
in RFC 2234 "Augmented BNF for Syntax Specifications: ABNF" [3].
NOTE: Comments like this provide additional nonessential
information about the rationale behind this document.
Such information is not needed for building a conformant
implementation, but may help those who wish to understand
the design in greater depth.
1.2 Discussion of this document media feature
information that indicates facilities assumed to be available
for the message content to be properly rendered or otherwise
presented. Media features are not intended to include
information that affects message transmission.
Discussion of this document should take place on the content feature set
negotiation and media feature registration mailing list hosted by some set of media features described by a media feature
the Internet Mail Consortium (IMC): assertion, as described in "A Syntax for Describing Media
Feature Sets" [1]. (See that memo for a more formal definition
of this term.)
Please send comments regarding this document to: feature set expression
a string that describes some feature set, formulated according
to the rules in "A Syntax for Describing Media Feature Sets"
[1] (and possibly extended by other specifications).
ietf-medfree@imc.org This specification uses syntax notation and conventions described in
RFC 2234 "Augmented BNF for Syntax Specifications: ABNF" [3].
To subscribe to this list, send a message with the body 'subscribe' NOTE: Comments like this provide additional nonessential
to "ietf-medfree-request@imc.org". information about the rationale behind this document. Such
information is not needed for building a conformant
implementation, but may help those who wish to understand the
design in greater depth.
To see what has gone on before you subscribed, please see the 2. Motivation and goals
mailing list archive at:
http://www.imc.org/ietf-medfree/ It is envisaged that media feature labelling of message parts may be
used in the following ways:
Internet draft Indicating media features for MIME content o to supply more detailed media feature information about a message
30 November 1999 content than can be provided by the 'Content-type:' header.
2. Motivation and goals o to provide summary media feature information (possibly including
MIME content types) about the content of a composite MIME message
part (e.g. 'multipart' or 'message'), without having to open up
the inner content of the message.
It is envisaged that media feature labelling of message parts may o to supply media feature information about external data referenced
be used in the following ways: by a message part (e.g. 'message/external-body' MIME type). This
information would not be available by examination of the message
content.
o to supply more detailed media feature information about a message o to describe the content of a message that is encrypted or encoded
content than can be provided by the 'Content-type:' header. using some application-specific file structure that hides the
content from a MIME processor. This information also would not be
generally available by examination of the message content.
o to provide summary media feature information (possibly including 3. The 'Content-features:' MIME header
MIME content types) about the content of a composite MIME message
part (e.g. 'multipart' or 'message'), without having to open up
the inner content of the message.
o to supply media feature information about external data A new header field is defined that extends the allowable formats for
referenced by a message part (e.g. 'message/external-body' MIME 'optional-field' [4] with the following syntax:
type). This information would not be available by examination of
the message content.
o to describe the content of a message that is encrypted or encoded optional-field =/ "Content-features" ":" Feature-expr
using some application-specific file structure that hides the Feature-expr = filter ; See [1], section 4.1
content from a MIME processor. This information also would not
be generally available by examination of the message content.
3. The 'Content-features:' MIME header where 'filter' is the media feature expression format defined by "A
Syntax for Describing Media Feature Sets" [1].
A new header field is defined that extends the allowable formats This header provides additional information about the message content
for 'optional-field' [4] with the following syntax: directly contained or indirectly referenced in the corresponding MIME
message part.
optional-field =/ "Content-features" ":" Feature-expr 3.1 Whitespace and folding long headers
Feature-expr = filter ; See [1], section 4.1
where 'filter' is the media feature expression format defined by "A In some circumstances, media feature expressions can be very long.
syntax for describing media feature sets" [1].
This header provides additional information about the message According to "A Syntax for Describing Media Feature Sets" [1],
content directly contained or indirectly referenced in the whitespace is allowed between lexical elements of a media feature
corresponding MIME message part. expression. Further, RFC822/MIME [4,5] allows folding of long
headers at points where whitespace appears to avoid line length
restrictions.
3.1 Usage considerations Therefore, it is recommended that whitespace is included as
permitted, especially in long media feature expressions, to
facilitate the folding of headers by agents that do not otherwise
understand the syntax of this field.
3.1.1 Simple message parts 3.2 Usage considerations
When applied to a simple MIME message part, the header should 3.2.1 Simple message parts
appear just once and is used to convey additional information about
the message part content that goes beyond that provided by the MIME
'Content-type:' header field. The 'Content-features:' header may
indicate a content type that is different than that given by the
MIME 'Content-type:' header. This is possible but not recommended
when applied to a non-composite body part: in any case, MIME
Internet draft Indicating media features for MIME content When applied to a simple MIME message part, the header should appear
30 November 1999 just once and is used to convey additional information about the
message part content that goes beyond that provided by the MIME
'Content-type:' header field. The 'Content-features:' header may
indicate a content type that is different than that given by the MIME
'Content-type:' header. This is possible but not recommended when
applied to a non-composite body part: in any case, MIME content type
processing must be performed in accordance with the 'Content-type:'
header.
content type processing must be performed in accordance with the NOTE: Once the message content has been delivered to an
'Content-type:' header. application, it is possible that subsequent processing may be
affected by content type information indicated by the media
feature expression. See example 4.5 below.
NOTE: Once the message content has been delivered to an 3.2.2 Multipart and other composites
application, it is possible that subsequent processing
may be affected by content type information indicated by
the media feature expression.
3.1.2 Multipart and other composites 'Content-features:' headers may be applied to a MIME multipart
indicating information about the inner content of the multipart.
'Content-features:' headers may be applied to a MIME multipart Implementations must not assume a one-to-one relationship between
indicating information about the inner content of the multipart. 'Content-features' headers and contained body parts. Headers may
No one-to-one relationship between headers and contained body parts appear on a containing multipart wrapper in a different order than
is assumed. the body parts to which they refer; a single header may refer to
more than one contained body part; several headers may refer to the
same contained body part.
If it is important to relate specific media features to specific If it is important to relate specific media features to specific
MIME body parts, then the 'Content-features:' header should be contained MIME body parts, then the 'Content-features:' header should
applied directly to the body part concerned, rather than the be applied directly to the body part concerned, rather than the
surrounding composite. surrounding composite.
NOTE: The intent here is to allow summary media feature NOTE: The intent here is to allow summary media feature
information to be provided without having to open up and information to be provided without having to open up and
examine the inner content of the MIME message. examine the inner content of the MIME message.
Similar usage may apply when the message format is a non-MIME or Similar usage may apply when the message format is a non-MIME or
opaque composite; e.g. 'application/zip', or an encrypted message. opaque composite; e.g. 'application/zip', or an encrypted message.
In these cases, the option of examining the message content to In these cases, the option of examining the message content to
discover media feature information is not available. discover media feature information is not available.
3.1.3 Reference to external data 3.2.3 Reference to external data
Media feature information about data indirectly referenced by a Media feature information about data indirectly referenced by a MIME
MIME body part rather than contained within message can be conveyed body part rather than contained within a message can be conveyed
using one or more 'Content-features:' headers. using one or more 'Content-features:' headers.
For example, media information --including contained MIME content For example, media information --including contained MIME content
type(s)-- about the data referenced by a MIME 'Message/external- type(s)-- about the data referenced by a MIME 'Message/external-body'
body' may be conveyed. may be conveyed.
4. Examples 4. Examples
4.1 Simple message 4.1 Simple message
Mime-Version: 1.0 Mime-Version: 1.0
Content-type: text/plain;charset=US-ASCII Content-type: text/plain;charset=US-ASCII
Content-features: (& (paper-size=A4) (ua-media=stationery) ) Content-features: (& (paper-size=A4) (ua-media=stationery) )
:
(data)
:
Internet draft Indicating media features for MIME content :
30 November 1999 (data)
:
4.2 Fax message 4.2 Fax message
Mime-Version: 1.0 Mime-Version: 1.0
Content-Type: multipart/mixed; boundary="break" Content-Type: multipart/mixed; boundary="break"
Content-features: Content-features:
(& (Type="image/tiff") (& (Type="image/tiff")
(color=Binary) (color=Binary)
(image-file-structure=TIFF-S) (image-file-structure=TIFF-S)
(dpi=200) (dpi=200)
(dpi-xyratio=200/100) (dpi-xyratio=200/100)
(paper-size=A4) (paper-size=A4)
(image-coding=MH) (MRC-mode=0) (image-coding=MH) (MRC-mode=0)
(ua-media=stationery) ) (ua-media=stationery) )
--break --break
Content-Type: image/tiff; name="coverpage.tiff" Content-Type: image/tiff; name="coverpage.tiff"
Content-Transfer-Encoding: base64 Content-Transfer-Encoding: base64
Content-Description: This part is a coverpage Content-Description: This part is a coverpage
Content-Disposition: attachment; filename="coverpage.tiff" Content-Disposition: attachment; filename="coverpage.tiff"
0M8R4KGxGuEAAAAAAAAAAAAAAAAAAAAAPgADAP7/CQAGAAAAAAAAAAAAAAA 0M8R4KGxGuEAAAAAAAAAAAAAAAAAAAAAPgADAP7/CQAGAAAAAAAAAAAAAAA
AAAAAAAAEAAAZAAAAAEAAAD+////AAAAAAAAAAD//////////////////// AAAAAAAAEAAAZAAAAAEAAAD+////AAAAAAAAAAD////////////////////
: :
(more data) (more data)
: :
--break --break
Content-Type: image/tiff; name="document.tiff"
Content-Transfer-Encoding: base64
Content-Disposition: attachment; filename="document.tiff"
AAAADgAAAA8AAAAQAAAAEQAAABIAAAATAAAAFAAAABUAAAAWAAAAFwAAABg Content-Type: image/tiff; name="document.tiff"
GgAAABsAAAAcAAAAHQAAAB4AAAAfAAAAIAAAACEAAAAiAAAAIwAAACQAAAA Content-Transfer-Encoding: base64
: Content-Disposition: attachment; filename="document.tiff"
(more data)
: AAAADgAAAA8AAAAQAAAAEQAAABIAAAATAAAAFAAAABUAAAAWAAAAFwAAABg
--break-- GgAAABsAAAAcAAAAHQAAAB4AAAAfAAAAIAAAACEAAAAiAAAAIwAAACQAAAA
:
(more data)
:
--break--
4.3 Multipart/alternative data 4.3 Multipart/alternative data
This example illustrates two points: This example illustrates three points:
o Information about the various parts in a multipart/alternative o Information about the various parts in a multipart/alternative can
can be made available before the alternative body parts are be made available before the alternative body parts are processed.
processed. This may facilitiate optimum one-pass processing of This may facilitiate optimum one-pass processing of
multipart/alternative data. multipart/alternative data.
o There may be alternatives having the same basic MIME content- o There may be alternatives having the same basic MIME content-type,
type, but differing in the content features that they use. but differing in the content features that they use.
Internet draft Indicating media features for MIME content o There is NO defined correspondence between 'Content-features'
30 November 1999 headers and contained body parts.
Mime-Version: 1.0 Mime-Version: 1.0
Content-Type: multipart/alternative; boundary="break" Content-Type: multipart/alternative; boundary="break"
Content-features: (& (Type="text/plain") (charset=US-ASCII) ) Content-features: (& (Type="text/plain") (charset=US-ASCII) )
Content-features: Content-features:
(& (Type="text/html") (charset=ISO-8859-1) (color=binary) ) (& (Type="text/html") (charset=ISO-8859-1) (color=limited) )
Content-features: Content-features:
(& (Type="text/html") (charset=ISO-8859-1) (color=limited) ) (& (Type="text/html") (charset=ISO-8859-1) (color=binary) )
--break --break
Content-type: "text/plain";charset="US-ASCII" Content-type: "text/plain";charset=US-ASCII
Content-features: (color=binary)
: :
(data) (data)
: :
--break --break
Content-type: text/html;charset="iso-8859-1" Content-type: "text/plain";charset=US-ASCII
Content-features: (color=binary) Content-features: (color=limited)
: :
(data) (data)
: :
--break --break
Content-type: text/html;charset="iso-8859-1"
Content-features: (color=limited)
: Content-type: text/html;charset=iso-8859-1
(data) Content-features: (color=binary)
:
--break--
4.4 Reference to external message data :
(data)
:
--break
Content-type: text/html;charset=iso-8859-1
Content-features: (color=limited)
Mime-Version: 1.0 :
Content-type: message/external-body; access-type=URL; (data)
URL="http://www.foo.com/file1.html" :
--break--
Content-type: Multipart/mixed 4.4 Reference to external message data
Content-features: (& (Type="text/plain") (charset=US-ASCII) )
Content-features: (& (Type="image/tiff") (color=limited) )
<end> Mime-Version: 1.0
Content-type: message/external-body; access-type=URL;
URL="http://www.foo.com/file1.html"
Internet draft Indicating media features for MIME content Content-type: Multipart/mixed
30 November 1999 Content-features: (& (Type="text/plain") (charset=US-ASCII) )
Content-features: (& (Type="image/tiff") (color=limited) )
<end>
4.5 Compressed data 4.5 Compressed data
This example shows how the "Content-features" header can be used to This example shows how the 'Content-features' header can be used to
overcome the problem noted in the MIME registration for overcome the problem noted in the MIME registration for
"Application/zip" regarding information about the data content. 'Application/zip' regarding information about the data content.
Mime-Version: 1.0 Mime-Version: 1.0
Content-type: application/zip Content-type: application/zip
Content-features: (& (Type="text/plain") (charset=US-ASCII) ) Content-features: (& (Type="text/plain") (charset=US-ASCII) )
Content-features: (& (Type="image/tiff") (color=limited) ) Content-features: (& (Type="image/tiff") (color=limited) )
Content-transfer-encoding: base64 Content-transfer-encoding: base64
: :
(data) (data)
: :
<end> <end>
4.6 Multipart/related data 4.6 Multipart/related data
(See also: RFC 2387, "The MIME Multipart/Related Content-type" [8]) (See also: RFC 2387, "The MIME Multipart/Related Content-type" [8])
Mime-Version: 1.0 Mime-Version: 1.0
Content-Type: multipart/related; boundary="boundary-example"; Content-Type: multipart/related; boundary="boundary-example";
type="text/html"; start="<foo3@foo1@bar.net>" type="text/html"; start="<foo3@foo1@bar.net>"
Content-features: (& (type="text/html") (charset=US-ASCII) ) Content-features: (& (type="text/html") (charset=US-ASCII) )
Content-features: (type="image/gif") Content-features: (type="image/gif")
--boundary-example --boundary-example
Content-Type: text/html;charset="US-ASCII" Content-Type: text/html;charset=US-ASCII
Content-ID: <foo3@foo1@bar.net> Content-ID: <foo3@foo1@bar.net>
... text of the HTML document, which might contain a URI referencing a resource in another body part, for example
referencing a resource in another body part, for example through a statement such as:
through a statement such as: <IMG SRC="http://www.ietf.cnri.reston.va.us/images/ietflogo.gif"
<IMG SRC="http://www.ietf.cnri.reston.va.us/images/ietflogo.gif" ALT="IETF logo">
ALT="IETF logo">
--boundary-example --boundary-example
Content-Location: Content-Location:
http://www.ietf.cnri.reston.va.us/images/ietflogo.gif http://www.ietf.cnri.reston.va.us/images/ietflogo.gif
Content-Type: IMAGE/GIF Content-Type: IMAGE/GIF
Content-Transfer-Encoding: BASE64 Content-Transfer-Encoding: BASE64
R0lGODlhGAGgAPEAAP/////ZRaCgoAAAACH+PUNvcHlyaWdodCAoQykgMTk5 R0lGODlhGAGgAPEAAP/////ZRaCgoAAAACH+PUNvcHlyaWdodCAoQykgMTk5
NSBJRVRGLiBVbmF1dGhvcml6ZWQgZHVwbGljYXRpb24gcHJvaGliaXRlZC4A NSBJRVRGLiBVbmF1dGhvcml6ZWQgZHVwbGljYXRpb24gcHJvaGliaXRlZC4A
etc... etc...
--boundary-example-- --boundary-example--
Internet draft Indicating media features for MIME content 5. Security Considerations
30 November 1999
5. Security considerations When applied to simple or multipart MIME formatted data, a media
feature expression provides summary information about the message
data, which in many cases can be determined by examination of the
message content. Under these circumstances, no additional security
considerations appear to be raised.
When applied to simple or multipart MIME formatted data, a media When applied to other message composites, especially encrypted
feature expression provides summary information about the message message content, feature expressions may disclose information that is
data, which in many cases can be determined by examination of the otherwise unavailable. In these cases, some security considerations
message content. Under these circumstances, no additional security associated with media content negotiation [1,2] may have greater
considerations appear to be raised. relevance.
When applied to other message composites, especially encrypted It is suggested here that media feature descriptions may be usefully
message content, feature expressions may disclose information that employed with encrypted message content. In doing this, take care to
is otherwise unavailable. In these cases, some security ensure that the purpose of encryption is not compromised (e.g.
considerations associated with media content negotiation [1,2] may encryption might be intended to conceal the fact that a particular
have greater relevance. application data format is being used, which fact might be disclosed
by an injudiciously applied Content-features header).
It is suggested here that media feature descriptions may be If a 'Content-features' header is applied to a multipart/signed
usefully employed with encrypted message content. In doing this, object (or indeed outside any other form of signed data) the media
take care to ensure that the purpose of encryption is not feature information is not protected. This unprotected information
compromised (e.g. encryption might be intended to conceal the fact could be tampered with, possibly fooling implementations into doing
that a particular application data format is being used, which fact inappropriate things with the contained material. (Putting the media
might be disclosed by an injudiciously applied Content-features feature information inside the signed information would overcome
header). this, at the cost of requiring implementations to parse the inner
structure to find it.)
6. Acknowledgements 6. Acknowledgements
This proposal draws from discussions with Dan Wing. The fax This proposal draws from discussions with Dan Wing. The fax message
message example was taken from a proposal by Mike Ruhl. The example was taken from a proposal by Mike Ruhl. The
multipart/related example is developed from RFC 2557. multipart/related example is developed from RFC 2557 [7].
The author would like to thank the following people who offered The author would like to thank the following people who offered
comments that led to significant improvements: Mr Hiroshi Tamura, comments that led to significant improvements: Mr Hiroshi Tamura,
Ted Hardie, Maurizio Codogno, Jacob Palme. Ted Hardie, Maurizio Codogno, Jacob Palme, Ned Freed.
7. References 7. References
[1] RFC 2533, "A syntax for describing media feature sets" [1] Klyne, G., "A Syntax for Describing Media Feature Sets", RFC
Graham Klyne, 5GM/Content Technologies 2533, March 1999.
March 1999.
[2] RFC 2506, "Media Feature Tag Registration Procedure"
Koen Holtman, TUE
Andrew Mutz, Hewlett-Packard
Ted Hardie, NASA
March 1999.
[3] RFC 2234, "Augmented BNF for Syntax Specifications: ABNF"
D. Crocker (editor), Internet Mail Consortium
P. Overell, Demon Internet Ltd.
November 1997.
Internet draft Indicating media features for MIME content
30 November 1999
[4] RFC 822, "Standard for the format of ARPA Internet text messages"
D. Crocker, Department of Electrical Engineering, University of
Delaware
August 1982.
To be replaced by:
"Internet Message Format Standard"
P. Resnick (editor), QUALCOMM Incorporated
Internet draft: <draft-ietf-drums-msg-fmt-07.txt>
Work in progress, January 1999.
[5] RFC 2045, "Multipurpose Internet Mail Extensions (MIME)
Part 1: Format of Internet message bodies"
N. Freed, Innosoft
N. Borenstein, First Virtual
November 1996.
[6] RFC 2046, "Multipurpose Internet Mail Extensions (MIME)
Part 2: Media types"
N. Freed, Innosoft
N. Borenstein, First Virtual
November 1996.
[7] RFC 2017, "Definition of the URL MIME External-Body Access-Type"
N. Freed, Innosoft
K. Moore, University of Tennessee
A. Cargille, WG Chair
October 1996
[8] RFC 2387, "The MIME Multipart/Related Content-type"
E. Levinson
August 1998
[9] "Registration of Charset and Languages Media Features Tags"
Paul Hoffman, IMC
Internet draft: <draft-hoffman-char-lang-media-01.txt>
Work in progress, July 1999.
8. Author's address
Graham Klyne
Content Technologies Ltd.
1220 Parkview,
Arlington Business Park
Theale
Reading, RG7 4SA
United Kingdom.
Telephone: +44 118 930 1300
Facsimile: +44 118 930 1301
E-mail: GK@ACM.ORG
Internet draft Indicating media features for MIME content [2] Holtman, K., Mutz, A. and T. Hardie, "Media Feature Tag
30 November 1999 Registration Procedure", RFC 2506, March 1999.
Full copyright statement [3] Crocker, D. and P. Overell, "Augmented BNF for Syntax
Specifications: ABNF", RFC 2234, November 1997.
Copyright (C) The Internet Society 1999. All Rights Reserved. [4] Crocker, D., "Standard for the format of ARPA Internet text
messages", STD 11, RFC 822, August 1982.
This document and translations of it may be copied and furnished to [5] Freed, N. and N. Borenstein, "Multipurpose Internet Mail
others, and derivative works that comment on or otherwise explain Extensions (MIME) Part 1: Format of Internet message bodies",
it or assist in its implementation may be prepared, copied, RFC 2045, November 1996.
published and distributed, in whole or in part, without restriction
of any kind, provided that the above copyright notice and this
paragraph are included on all such copies and derivative works.
However, this document itself may not be modified in any way, such
as by removing the copyright notice or references to the Internet
Society or other Internet organizations, except as needed for the
purpose of developing Internet standards in which case the
procedures for copyrights defined in the Internet Standards process
must be followed, or as required to translate it into languages
other than English.
The limited permissions granted above are perpetual and will not be [6] Levinson, E., "The MIME Multipart/Related Content-type", RFC
revoked by the Internet Society or its successors or assigns. 2387, August 1998.
This document and the information contained herein is provided on [7] Palme, J., Hopmann, A. and N. Shelness, "MIME Encapsulation of
an "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET Aggregate Documents, such as HTML (MHTML)", RFC 2557, March
ENGINEERING TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR 1999.
IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF
THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
Revision history 8. Author's Address
[[[RFC editor: please remove this section on publication]]] Graham Klyne
Content Technologies Ltd.
1220 Parkview,
Arlington Business Park
Theale
Reading, RG7 4SA
United Kingdom
00a 10-Feb-1999 Initial draft. Phone: +44 118 930 1300
Fax: +44 118 930 1301
EMail: GK@ACM.ORG
01a 16-Feb-1999 Added pointers to mailing list for discussion. 9. Full Copyright Statement
01b 04-Mar-1999 Various editorial changes. Added placeholder for Copyright (C) The Internet Society (2000). All Rights Reserved.
multipart/related example.
01c 13-Apr-1999 Separated multipart/alternative and This document and translations of it may be copied and furnished to
message/external-body into separate examples. others, and derivative works that comment on or otherwise explain it
Added example for compressed data. Added example or assist in its implementation may be prepared, copied, published
for multipart/related data. Updated references. and distributed, in whole or in part, without restriction of any
kind, provided that the above copyright notice and this paragraph are
included on all such copies and derivative works. However, this
document itself may not be modified in any way, such as by removing
the copyright notice or references to the Internet Society or other
Internet organizations, except as needed for the purpose of
developing Internet standards in which case the procedures for
copyrights defined in the Internet Standards process must be
followed, or as required to translate it into languages other than
English.
02a 20-Jul-1999 Incorporated review comments -- editorial changes. The limited permissions granted above are perpetual and will not be
revoked by the Internet Society or its successors or assigns.
02b 29-Nov-1999 Added (charset=...) to (type=text/*) examples. This document and the information contained herein is provided on an
Added citation to charset and language feature "AS IS" basis and THE INTERNET SOCIETY AND THE INTERNET ENGINEERING
registration document. TASK FORCE DISCLAIMS ALL WARRANTIES, EXPRESS OR IMPLIED, INCLUDING
BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMATION
HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
Internet draft Indicating media features for MIME content Acknowledgement
30 November 1999
02c 29-Nov-1999 Indicated motivation for multipart/alternative Funding for the RFC Editor function is currently provided by the
example. Moved copyright section to end of text. Internet Society.
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