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INTERNET DRAFT                         E. J. Whitehead, Jr., UC Irvine
<draft-whitehead-mime-xml-04>      M. Murata, Fuji Xerox Info. Systems

Expires November, 1998                                    May 31, 1998



                            XML Media Types

Status of this Memo

   This document is an Internet-Draft. 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
   months and may be updated, replaced, or made obsolete 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".

   To learn the current status of any Internet-Draft, please check the
   "1id-abstracts.txt" listing contained in the Internet-Drafts Shadow
   Directories on ftp.is.co.za (Africa), nic.nordu.net (Europe),
   munnari.oz.au (Pacific Rim), ftp.ietf.org (US East Coast), or
   ftp.isi.edu (US West Coast).

   Distribution of this document is unlimited.

Copyright Notice

   Copyright (C) The Internet Society (1998). All Rights Reserved.

Abstract

   This document proposes two new media subtypes, text/xml and
   application/xml, for use in exchanging network entities which are
   conforming Extensible Markup Language (XML). XML entities are
   currently exchanged via the HyperText Transfer Protocol on the World
   Wide Web, are an integral part of the WebDAV protocol for remote web
   authoring, and are expected to have utility in many domains.
















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Contents

STATUS OF THIS MEMO...................................................1
COPYRIGHT NOTICE......................................................1
ABSTRACT..............................................................1
CONTENTS..............................................................2
1 INTRODUCTION .......................................................3
2 NOTATIONAL CONVENTIONS .............................................3
3 XML MEDIA TYPES ....................................................4
3.1  Text/xml Registration ...........................................4
3.2  Application/xml Registration ....................................7
4 SECURITY CONSIDERATIONS ............................................9
5 THE BYTE ORDER MARK (BOM) AND CONVERSIONS TO/FROM UTF-16 ..........10
6 EXAMPLES ..........................................................10
6.1  text/xml with UTF-8 Charset ....................................10
6.2  text/xml with UTF-16 Charset ...................................11
6.3  text/xml with ISO-2022-KR Charset ..............................11
6.4  text/xml with Omitted Charset ..................................11
6.5  application/xml with UTF-16 Charset ............................12
6.6  application/xml with ISO-2022-KR Charset .......................12
6.7  application/xml with Omitted Charset and UTF-16 XML Entity .....12
6.8  application/xml with Omitted Charset and UTF-8 Entity ..........13
6.9  application/xml with Omitted Charset and Internal Encoding
Declaration..........................................................13
7 REFERENCES ........................................................14
8 ACKNOWLEDGEMENTS ..................................................15
9 ADDRESSES OF AUTHORS ..............................................15





























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1  Introduction

   The World Wide Web Consortium (W3C) has issued a Recommendation
   [REC-XML] which defines the Extensible Markup Language (XML),
   version 1. To enable the exchange of XML network entities, this
   document proposes two new media types, text/xml and application/xml.

   XML entities are currently exchanged on the World Wide Web, and XML
   is also used for property values and parameter marshalling by the
   WebDAV protocol for remote web authoring. Thus, there is a need for
   a media type to properly label the exchange of XML network entities.
   (Note that, as sometimes happens between two communities, both MIME
   and XML have defined the term entity, with different meanings.)

   Although XML is a subset of the Standard Generalized Markup Language
   (SGML) [ISO-8897], and currently is assigned the media types
   text/sgml and application/sgml, there are several reasons why use of
   text/sgml or application/sgml to label XML is inappropriate. First,
   there exist many applications which can process XML, but which
   cannot process SGML, due to SGML's larger feature set. Second, SGML
   applications cannot always process XML entities, because XML uses
   features of recent technical corrigenda to SGML.  Third, the
   definition of text/sgml and application/sgml [RFC-1874] includes
   parameters for SGML bit combination transformation format (SGML-
   bctf), and SGML boot attribute (SGML-boot). Since XML does not use
   these parameters, it would be ambiguous if such parameters were
   given for an XML entity. For these reasons, the best approach for
   labeling XML network entities is to provide new media types for XML.

   Since XML is an integral part of the WebDAV Distributed Authoring
   Protocol, and since World Wide Web Consortium Recommendations have
   conventionally been assigned IETF tree media types, and since
   similar media types (HTML, SGML) have been assigned IETF tree media
   types, the XML media types also belong in the IETF media types tree.


2  Notational Conventions

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in [RFC-2119].












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3  XML Media Types

   This document introduces two new media types for XML entities,
   text/xml and application/xml.  Registration information for these
   media types are described in the sections below.

   Every XML entity is suitable for use with the application/xml media
   type without modification.  But this does not exploit the fact that
   XML can be treated as plain text in many cases.  MIME user agents
   (and web user agents) that do not have explicit support for
   application/xml will treat it as application/octet-stream, for
   example, by offering to save it to a file.

   To indicate that an XML entity should be treated as plain text by
   default, use the text/xml media type.  This restricts the encoding
   used in the XML entity to those that are compatible with the
   requirements for text media types as described in [RFC-2045] and
   [RFC-2046], e.g., UTF-8, but not UTF-16 (except for HTTP).

   XML provides a general framework for defining sequences of
   structured data.  In some cases, it may be desirable to define new
   media types which use XML but define a specific application of XML,
   perhaps due to domain-specific security considerations or runtime
   information. This document does not prohibit future media types
   dedicated to such XML applications. However, developers of such
   media types are recommended to use this document as a basis.  In
   particular, the charset parameter should be used in the same manner.

   Within the XML specification, XML entities can be classified into
   four types.  In the XML terminology, they are called "document
   entities", "external DTD subsets", "external parsed entities", and
   "external parameter entities".  The media types text/xml and
   application/xml can be used for any of these four types.


3.1 Text/xml Registration

   MIME media type name: text

   MIME subtype name: xml

   Mandatory parameters: none

   Optional parameters: charset

       Although listed as an optional parameter, the use of the charset
       parameter is STRONGLY RECOMMENDED, since this information can be
       used by XML processors to determine authoritatively the
       character encoding of the XML entity. The charset parameter can
       also be used to provide protocol-specific operations, such as
       charset-based content negotiation in HTTP.


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       "UTF-8" [RFC-2279] is the recommended value, representing the
       UTF-8 charset. UTF-8 is supported by all conforming XML
       processors [REC-XML].

       If the XML entity is transmitted via HTTP, which uses a MIME-
       like mechanism that is exempt from the restrictions on the text
       top-level type (see section 19.4.1 of HTTP 1.1 [RFC-2068]),
       "UTF-16"  (Appendix C.3 of [UNICODE] and Amendment 1 of [ISO-
       10646]) is also recommended. UTF-16 is supported by all
       conforming XML processors [REC-XML].  Since the handling of CR,
       LF and NUL for text types in most MIME applications would cause
       undesired transformations of individual octets in UTF-16 multi-
       octet characters, gateways from HTTP to these MIME applications
       MUST transform the XML entity from a text/xml; charset="utf-16"
       to application/xml; charset="utf-16".

       Conformant with [RFC-2046], if a text/xml entity is received
       with the charset parameter omitted, MIME processors and XML
       processors MUST use the default charset value of "us-ascii". If
       the XML entity is transmitted via HTTP, the default charset
       value is "ISO-8859-1" (see section 3.7.1 of HTTP 1.1 [RFC-
       2068]).

       Since the charset parameter is authoritative, the charset is not
       always declared within an XML encoding declaration.  Thus,
       special care is needed when the recipient strips the MIME header
       and provides persistent storage of the received XML entity
       (e.g., in a file system). Unless the charset is UTF-8 or UTF-16,
       the recipient SHOULD also persistently store information about
       the charset, perhaps by embedding a correct XML encoding
       declaration within the XML entity.

   Encoding considerations:

       This media type MAY be encoded as appropriate for the charset
       and the capabilities of the underlying MIME transport. For 7-bit
       transports, data in both UTF-8 and UTF-16 is encoded in quoted-
       printable or base64.  For 8-bit clean transport (e.g., ESMTP,
       8BITMIME, or NNTP), UTF-8 is not encoded, but UTF-16 is base64
       encoded.  For binary clean transports (e.g., HTTP), no content-
       transfer-encoding is necessary.

   Security considerations:

       See section 4 below.

   Interoperability considerations:

       XML has proven to be interoperable across WebDAV clients and
       servers, and for import and export from multiple XML authoring
       tools.


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   Published specification: see [REC-XML]

   Applications which use this media type:

       XML is device-, platform-, and vendor-neutral and is supported
       by a wide range of Web user agents, WebDAV clients and servers,
       as well as XML authoring tools.

   Additional information:

       Magic number(s): none

       Although no byte sequences can be counted on to always be
       present, XML entities in ASCII-compatible charsets (including
       UTF-8) often begin with hexadecimal 3C 3F 78 6D 6C ("<?xml").
       For more information, see Appendix F of [REC-XML].

       File extension(s): .xml, .dtd
       Macintosh File Type Code(s): "TEXT"

   Person & email address for further information:

       Dan Connolly <connolly@w3.org>
       Murata Makoto (Family Given) <murata@fxis.fujixerox.co.jp>

   Intended usage: COMMON

   Author/Change controller:

       The XML specification is a work product of the World Wide Web
       Consortium's XML Working Group, and was edited by:

       Tim Bray <tbray@textuality.com>
       Jean Paoli <jeanpa@microsoft.com>
       C. M. Sperberg-McQueen <cmsmcq@uic.edu>

       The W3C, and the W3C XML working group, has change control over
       the XML specification.















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3.2 Application/xml Registration

   MIME media type name: application

   MIME subtype name: xml

   Mandatory parameters: none

   Optional parameters: charset

       Although listed as an optional parameter, the use of the charset
       parameter is STRONGLY RECOMMENDED, since this information can be
       used by XML processors to determine authoritatively the charset
       of the XML entity. The charset parameter can also be used to
       provide protocol-specific operations, such as charset-based
       content negotiation in HTTP.

       "UTF-8" [RFC-2279] and "UTF-16" (Appendix C.3 of [UNICODE] and
       Amendment 1 of [ISO-10646]) are the recommended values,
       representing the UTF-8 and UTF-16 charsets, respectively. These
       charsets are  preferred since they are supported by all
       conforming XML processors [REC-XML].

       If an application/xml entity is received where the charset
       parameter is omitted, no information is being provided about the
       charset by the MIME Content-Type header. Conforming XML
       processors MUST follow the requirements in section 4.3.3 of
       [REC-XML] which directly address this contingency. However, MIME
       processors which are not XML processors should not assume a
       default charset if the charset parameter is omitted from an
       application/xml entity.

       Since the charset parameter is authoritative, the charset is not
       always declared within an XML encoding declaration.  Thus,
       special care is needed when the recipient strips the MIME header
       and provides persistent storage of the received XML entity
       (e.g., in a file system).  Unless the charset is UTF-8 or
       UTF-16, the recipient SHOULD also persistently store information
       about the charset, perhaps by embedding a correct XML encoding
       declaration within the XML entity.

   Encoding considerations:

       This media type MAY be encoded as appropriate for the charset
       and the capabilities of the underlying MIME transport. For 7-bit
       transports, data in both UTF-8 and UTF-16 is encoded in quoted-
       printable or base64.  For 8-bit clean transport (e.g., ESMTP,
       8BITMIME, or NNTP), UTF-8 is not encoded, but UTF-16 is base64
       encoded.  For binary clean transport (e.g., HTTP), no content-
       transfer-encoding is necessary.




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   Security considerations:

       See section 4 below.

   Interoperability considerations:

       XML has proven to be interoperable for import and export from
       multiple XML authoring tools.

   Published specification: see [REC-XML]

   Applications which use this media type:

       XML is device-, platform-, and vendor-neutral and is supported
       by a wide range of Web user agents and XML authoring tools.

   Additional information:

       Magic number(s): none

       Although no byte sequences can be counted on to always be
       present, XML entities in ASCII-compatible charsets (including
       UTF-8) often begin with hexadecimal 3C 3F 78 6D 6C ("<?xml"),
       and those in UTF-16 often begin with hexadecimal FE FF 00 3C 00
       3F 00 78 00 6D or FF FE 3C 00 3F 00 78 00 6D 00 (the Byte Order
       Mark (BOM) followed by "<?xml").  For more information, see
       Annex F of [REC-XML].

       File extension(s): .xml, .dtd
       Macintosh File Type Code(s): "TEXT"

   Person & email address for further information:

       Dan Connolly <connolly@w3.org>
       Murata Makoto (Family Given) <murata@fxis.fujixerox.co.jp>

   Intended usage: COMMON

   Author/Change controller:

       The XML specification is a work product of the World Wide Web
       Consortium's XML Working Group, and was edited by:

       Tim Bray <tbray@textuality.com>
       Jean Paoli <jeanpa@microsoft.com>
       C. M. Sperberg-McQueen <cmsmcq@uic.edu>

       The W3C, and the W3C XML working group, has change control over
       the XML specification.




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4  Security Considerations

   XML, as a subset of SGML, has the same security considerations as
   specified in [RFC-1874].

   To paraphrase section 3 of [RFC-1874], XML entities contain
   information to be parsed and processed by the recipient's XML
   system.  These entities may contain and such systems may permit
   explicit system level commands to be executed while processing the
   data.  To the extent that an XML system will execute arbitrary
   command strings, recipients of XML entities may be at risk. In
   general, it may be possible to specify commands that perform
   unauthorized file operations or make changes to the display
   processor's environment that affect subsequent operations.

   Use of XML is expected to be varied, and widespread.  XML is under
   scrutiny by a wide range of communities for use as a common syntax
   for community-specific metadata.  For example, the Dublin Core group
   is using XML for document metadata, and a new effort has begun which
   is considering use of XML for medical information.  Other groups
   view XML as a mechanism for marshalling parameters for remote
   procedure calls.  More uses of XML will undoubtedly arise.

   Security considerations will vary by domain of use.  For example,
   XML medical records will have much more stringent privacy and
   security considerations than XML library metadata. Similarly, use of
   XML as a parameter marshalling syntax necessitates a case by case
   security review.

   XML may also have some of the same security concerns as plain text.
   Like plain text, XML can contain escape sequences which, when
   displayed, have the potential to change the display processor
   environment in ways that adversely affect subsequent operations.
   Possible effects include, but are not limited to, locking the
   keyboard, changing display parameters so subsequent displayed text
   is unreadable, or even changing display parameters to deliberately
   obscure or distort subsequent displayed material so that its meaning
   is lost or altered.  Display processors should either filter such
   material from displayed text or else make sure to reset all
   important settings after a given display operation is complete.

   Some terminal devices have keys whose output, when pressed, can be
   changed by sending the display processor a character sequence. If
   this is possible the display of a text object containing such
   character sequences could reprogram keys to perform some illicit or
   dangerous action when the key is subsequently pressed by the user.
   In some cases not only can keys be programmed, they can be triggered
   remotely, making it possible for a text display operation to
   directly perform some unwanted action. As such, the ability to
   program keys should be blocked either by filtering or by disabling
   the ability to program keys entirely.


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   Note that it is also possible to construct XML documents which make
   use of what XML terms "entity references" (using the XML meaning of
   the term "entity", which differs from the MIME definition of this
   term), to construct repeated expansions of text. Recursive
   expansions are prohibited [REC-XML] and XML processors are required
   to detect them.  However, even non-recursive expansions may cause
   problems with the finite computing resources of computers, if they
   are performed many times.


5  The Byte Order Mark (BOM) and Conversions to/from UTF-16

   The XML Recommendation, in section 4.3.3, specifies that UTF-16 XML
   entities must begin with a byte order mark (BOM), which is the ZERO
   WIDTH NO-BREAK SPACE character, hexadecimal sequence 0xFEFF (or
   0xFFFE, depending on endian). The XML Recommendation further states
   that the BOM is an encoding signature, and is not part of either the
   markup or the character data of the XML document.

   Due to the BOM, applications which convert XML from the UTF-16
   encoding to another encoding SHOULD strip the BOM before conversion.
   Similarly, when converting from another encoding into UTF-16, the
   BOM SHOULD be added after conversion is complete.


6  Examples

   The examples below give the value of the Content-type MIME header
   and the XML declaration (which includes the encoding declaration)
   inside the XML entity.  For UTF-16 examples, the Byte Order Mark
   character is denoted as "{BOM}", and the XML declaration is assumed
   to come at the beginning of the XML entity, immediately following
   the BOM. Note that other MIME headers may be present, and the XML
   entity may contain other data in addition to the XML declaration;
   the examples focus on the Content-type header and the encoding
   declaration for clarity.


6.1 text/xml with UTF-8 Charset

   Content-type: text/xml; charset="utf-8"

   <?xml version="1.0" encoding="utf-8"?>

   This is the recommended charset value for use with text/xml.  Since
   the charset parameter is provided, MIME and XML processors must
   treat the enclosed entity as UTF-8 encoded.

   If sent using a 7-bit transport (e.g. SMTP), the XML entity must use
   a content-transfer-encoding of either quoted-printable or base64.
   For an 8-bit clean transport (e.g., ESMTP, 8BITMIME, or NNTP), or a


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   binary clean transport (e.g., HTTP) no content-transfer-encoding is
   necessary.


6.2 text/xml with UTF-16 Charset

   Content-type: text/xml; charset="utf-16"

   {BOM}<?xml version='1.0' encoding='utf-16'?>

   This is possible only when the XML entity is transmitted via HTTP,
   which uses a MIME-like mechanism and is a binary-clean protocol,
   hence does not perform CR and LF transformations and allows NUL
   octets. This differs from typical text MIME type processing (see
   section 19.4.1 of HTTP 1.1 [RFC-2068] for details).

   Since HTTP is binary clean, no content-transfer-encoding is
   necessary.


6.3 text/xml with ISO-2022-KR Charset

   Content-type: text/xml; charset="iso-2022-kr"

   <?xml version="1.0" encoding='iso-2022-kr'?>

   This example shows text/xml with a Korean charset (e.g., Hangul)
   encoded following the specification in [RFC-1557].  Since the
   charset parameter is provided, MIME and XML processors must treat
   the enclosed entity as encoded per [RFC-1557].

   Since ISO-2022-KR has been defined to use only 7 bits of data, no
   content-transfer-encoding is necessary with any transport.


6.4 text/xml with Omitted Charset

   Content-type: text/xml

   {BOM}<?xml version="1.0" encoding="utf-16"?>

   This example shows text/xml with the charset parameter omitted.  In
   this case, MIME and XML processors must assume the charset is
   "us-ascii", the default charset value for text media types specified
   in [RFC-2046], except when the underlying transport defines a
   different default charset, e.g., if the XML entity is transmitted
   via HTTP, the default charset value is "ISO-8859-1" (see section
   3.7.1 of HTTP 1.1 [RFC-2068]).

   Omitting the charset parameter is NOT RECOMMENDED for text/xml. For
   example, even if the contents of the XML entity are UTF-16 or UTF-8,


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   or the XML entity has an explicit encoding declaration, XML and MIME
   processors must assume the charset is "us-ascii".


6.5 application/xml with UTF-16 Charset

   Content-type: application/xml; charset="utf-16"

   {BOM}<?xml version="1.0"?>

   This is a recommended charset value for use with application/xml.
   Since the charset parameter is provided, MIME and XML processors
   must treat the enclosed entity as UTF-16 encoded.

   If sent using a 7-bit transport (e.g., SMTP) or an 8-bit clean
   transport (e.g., ESMTP, 8BITMIME, or NNTP), the XML entity must be
   encoded in quoted-printable or base64. For a binary clean transport
   (e.g., HTTP), no content-transfer-encoding is necessary.


6.6 application/xml with ISO-2022-KR Charset

   Content-type: application/xml; charset="iso-2022-kr"

   <?xml version="1.0" encoding="iso-2022-kr"?>

   This example shows application/xml with a Korean charset (e.g.,
   Hangul) encoded following the specification in [RFC-1557].  Since
   the charset parameter is provided, MIME and XML processors must
   treat the enclosed entity as encoded per [RFC-1557], independent of
   whether the XML entity has an internal encoding declaration (this
   example does show such a declaration, which agrees with the charset
   parameter).

   Since ISO-2022-KR has been defined to use only 7 bits of data, no
   content-transfer-encoding is necessary with any transport.


6.7 application/xml with Omitted Charset and UTF-16 XML Entity

   Content-type: application/xml

   {BOM}<?xml version='1.0'?>

   For this example, the XML entity begins with a BOM.  Since the
   charset has been omitted, a conforming XML processor follows the
   requirements of [REC-XML], section 4.3.3. Specifically, the XML
   processor reads the BOM, and thus knows deterministically that the
   charset encoding is UTF-16.

   An XML-unaware MIME processor should make no assumptions about the
   charset of the XML entity.

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6.8 application/xml with Omitted Charset and UTF-8 Entity

   Content-type: application/xml

   <?xml version='1.0'?>

   In this example, the charset parameter has been omitted, and there
   is no BOM. Since there is no BOM, the XML processor follows the
   requirements in section 4.3.3, and optionally applies the mechanism
   described in appendix F (which is non-normative) of [REC-XML] to
   determine the charset encoding of UTF-8. The XML entity does not
   contain an encoding declaration, but since the encoding is UTF-8,
   this is still a conforming XML entity.

   An XML-unaware MIME processor should make no assumptions about the
   charset of the XML entity.


6.9 application/xml with Omitted Charset and Internal Encoding
    Declaration

   Content-type: application/xml

   <?xml version='1.0' encoding="ISO-10646-UCS-4"?>

   In this example, the charset parameter has been omitted, and there
   is no BOM.  However, the XML entity does have an encoding
   declaration inside the XML entity which specifies the entity's
   charset. Following the requirements in section 4.3.3, and optionally
   applying the mechanism described in appendix F (non-normative) of
   [REC-XML], the XML processor determines the charset encoding of the
   XML entity (in this example, UCS-4).

   An XML-unaware MIME processor should make no assumptions about the
   charset of the XML entity.


















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7  References

   [ISO-10646] ISO/IEC, Information Technology -- Universal Multiple-
   Octet Coded Character Set (UCS) -- Part 1: Architecture and Basic
   Multilingual Plane, May 1993.

   [ISO-8897] ISO (International Organization for Standardization) ISO
   8879:1986(E) Information Processing -- Text and Office Systems --
   Standard Generalized Markup Language (SGML). First edition -- 1986-
   10-15.

   [REC-XML] T. Bray, J. Paoli, C. M. Sperberg-McQueen, "Extensible
   Markup Language (XML)" World Wide Web Consortium Recommendation REC-
   xml-19980210. http://www.w3.org/TR/1998/REC-xml-19980210.

   [RFC-1557] U. Choi, K. Chon, H. Park. "Korean Character Encoding for
   Internet Messages" KAIST, Solvit Chosun Media. RFC 1557. December,
   1993.

   [RFC-1874] E. Levinson. "SGML Media Types" Accurate Information
   Systems. RFC 1874. December, 1995.

   [RFC-2119] S. Bradner. "Key words for use in RFCs to Indicate
   Requirement Levels." RFC 2119, BCP 14. Harvard University. March,
   1997.

   [RFC-2045] N. Freed, N. Borenstein. "Multipurpose Internet Mail
   Extensions (MIME) Part One: Format of Internet Message Bodies"
   Innosoft, First Virtual. RFC 2045. November, 1996.

   [RFC-2046] N. Freed, N. Borenstein. "Multipurpose Internet Mail
   Extensions (MIME) Part Two: Media Types" Innosoft, First Virtual.
   RFC 2046. November, 1996.

   [RFC-2068] R. Fielding, J. Gettys, J. Mogul, H. Frystyk, T. Berners-
   Lee. "Hypertext Transfer Protocol -- HTTP/1.1" UC Irvine, DEC,
   MIT/LCS. RFC 2068. January, 1997.

   [RFC-2279] F. Yergeau, "UTF-8, a transformation format of ISO 10646"
   RFC 2279. January 1998.

   [UNICODE] The Unicode Consortium, "The Unicode Standard -- Version
   2.0", Addison-Wesley, 1996.










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8  Acknowledgements

   Chris Newman and Yaron Y. Goland both contributed content to the
   security considerations section of this document.  In particular,
   some text in the security considerations section is copied verbatim
   from draft-newman-mime-textpara-00, by permission of the author.
   Chris Newman additionally contributed content to the encoding
   considerations sections. Dan Connolly contributed content discussing
   when to use text/xml. Discussions with Ned Freed and Dan Connolly
   helped refine the author's understanding of the text media type;
   feedback from Larry Masinter was also very helpful in understanding
   media type registration issues.

   Members of the W3C XML Working Group and XML Special Interest group
   have made significant contributions to this document, and the
   authors would like to specially recognize James Clark, Martin
   Duerst, Rick Jelliffe, Gavin Nicol for their many thoughtful
   comments.


9  Addresses of Authors

   E. James Whitehead, Jr.
   Dept. of Information and Computer Science
   University of California, Irvine
   Irvine, CA 92697-3425
   Email: ejw@ics.uci.edu

   Murata Makoto (Family Given)
   Fuji Xerox Information Systems,
   KSP 9A7, 2-1, Sakado 3-chome, Takatsu-ku,
   Kawasaki-shi, Kanagawa-ken,
   213 Japan
   Email: murata@fxis.fujixerox.co.jp



















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