Update to MIME regarding Charset Parameter Handling in Textual Media Types
draft-ietf-appsawg-mime-default-charset-00

The information below is for an old version of the document
Document Type Active Internet-Draft (appsawg WG)
Last updated 2012-03-23 (latest revision 2012-02-01)
Replaces draft-melnikov-mime-default-charset
Stream IETF
Intended RFC status Proposed Standard
Formats plain text pdf html
Stream WG state WG Document
Document shepherd Murray Kucherawy
IESG IESG state AD is watching
Telechat date
Responsible AD Pete Resnick
Send notices to appsawg-chairs@tools.ietf.org, draft-ietf-appsawg-mime-default-charset@tools.ietf.org
Applications Area Working Group                              A. Melnikov
Internet-Draft                                             Isode Limited
Updates: 2046 (if approved)                                   J. Reschke
Intended status: Standards Track                              greenbytes
Expires: August 4, 2012                                 February 1, 2012

         Update to MIME regarding Charset Parameter Handling in
                          Textual Media Types
               draft-ietf-appsawg-mime-default-charset-00

Abstract

   This document changes RFC 2046 rules regarding default charset
   parameter values for text/* media types to better align with common
   usage by existing clients and servers.

Status of this Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

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   This Internet-Draft will expire on August 4, 2012.

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   document authors.  All rights reserved.

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Table of Contents

   1.          Introduction and Overview . . . . . . . . . . . . . . . 3
   2.          Conventions Used in This Document . . . . . . . . . . . 3
   3.          New rules for default charset parameter values for
               text/* media types  . . . . . . . . . . . . . . . . . . 3
   4.          Default charset parameter value for text/plain
               media type  . . . . . . . . . . . . . . . . . . . . . . 4
   5.          Security Considerations . . . . . . . . . . . . . . . . 4
   6.          IANA Considerations . . . . . . . . . . . . . . . . . . 4
   7.          References  . . . . . . . . . . . . . . . . . . . . . . 4
   7.1.        Normative References  . . . . . . . . . . . . . . . . . 4
   7.2.        Informative References  . . . . . . . . . . . . . . . . 5
   Appendix A. Acknowledgements  . . . . . . . . . . . . . . . . . . . 5
               Authors' Addresses  . . . . . . . . . . . . . . . . . . 5

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1.  Introduction and Overview

   [RFC2046] specified that the default charset parameter (i.e. the
   value used when it is not specified) is "US-ASCII".  [RFC2616]
   changed the default for use by HTTP to be "ISO-8859-1".  This
   encoding is not very common for new text/* media types and a special
   rule in HTTP adds confusion about which specification ([RFC2046] or
   [RFC2616]) is authoritative in regards to the default charset for
   text/* media types. [[anchor2: At the time of writing of this
   document the IETF HTTPBIS WG is working on an update to RFC 2616
   which removes the default charset of "ISO-8859-1" for "text/*" media
   types.  It is expected that the set of HTTPBIs documents will
   reference this document in order to use the updated rules of default
   charset in "text/*" media types.]]

   Many complex text subtypes such as text/html [RFC2854] and text/xml
   [RFC3023] have internal (to their format) means of describing the
   charset.  Many existing User Agents ignore the default of "US-ASCII"
   rule for at least text/html and text/xml.

   This document changes RFC 2046 rules regarding default charset
   parameter values for text/* media types to better align with common
   usage by existing clients and servers.

2.  Conventions Used in This Document
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