Deprecating Unicode Language Tag Characters: RFC 2482 is Historic

Abstract

RFC 2482, "Language Tagging in Unicode Plain Text", describes a mechanism for using special Unicode language tag characters to identify languages when needed without more general markup such as that provided by XML. The Unicode Consortium has deprecated that facility and strongly recommends against its use. RFC 2482 has been moved to Historic status to reduce the possibility that Internet implementers would consider that system an appropriate mechanism for identifying languages.

Status of This Memo

This document is not an Internet Standards Track specification; it is published for informational purposes.

This document is a product of the Internet Engineering Task Force (IETF). It represents the consensus of the IETF community. It has received public review and has been approved for publication by the Internet Engineering Steering Group (IESG). Not all documents approved by the IESG are a candidate for any level of Internet Standard; see Section 2 of RFC 5741.

Information about the current status of this document, any errata, and how to provide feedback on it may be obtained at http://www.rfc-editor.org/info/rfc6082.

Copyright Notice

Copyright © 2010 IETF Trust and the persons identified as the document authors. All rights reserved.

This document is subject to BCP 78 and the IETF Trust's Legal Provisions Relating to IETF Documents (http://trustee.ietf.org/license-info) in effect on the date of publication of this document. Please review these documents carefully, as they describe your rights and restrictions with respect to this document. Code Components extracted from this document must include Simplified BSD License text as described in Section 4.e of the Trust Legal Provisions and are provided without warranty as described in the Simplified BSD License.

Table of Contents

   1. Introduction ....................................................2
   2. Action ..........................................................2
   3. Security Considerations .........................................3
   4. Acknowledgments .................................................3
   5. References ......................................................3
   
      5.1. Normative References .......................................3
      5.2. Informative References .....................................3

1. Introduction

RFC 2482, "Language Tagging in Unicode Plain Text" [RFC2482], describes a mechanism for using special Unicode language tag characters to identify languages when needed. It is an idea whose time never quite came. It has been superseded by whole-transaction language identification such as the MIME Content-language header [RFC3282] and more general markup mechanisms such as those provided by XML. The Unicode Consortium has deprecated the language tag character facility and strongly recommends against its use. RFC 2482 has been moved to Historic status to reduce the possibility that Internet implementers would consider that tagging system an appropriate mechanism for identifying languages.

A discussion of the status of the language tag characters and their applicability appears in Section 16.9 of The Unicode Standard [Unicode52].

2. Action

RFC 2482 has been deprecated and reclassified as Historic. Internet protocols and Standards-Track documents should not use the facilities described in that document.

3. Security Considerations

By deprecating RFC 2482, we eliminate a facility that is no longer encouraged or supported by the Unicode Consortium and that may have been slightly risky in use if misinterpreted or if expectations of support were not met. So, if this action has any effect on Internet security at all, it should be positive.

4. Acknowledgments

Helpful comments were received from Peter Koch and S. Moonesamy.

5. References

5.1. Normative References

   [RFC2482]    Whistler, K. and G. Adams, "Language Tagging in Unicode
                Plain Text", RFC 2482, January 1999.
   
   [Unicode52]  The Unicode Consortium.  The Unicode Standard, Version
                5.2.0, defined by: "The Unicode Standard, Version
                5.2.0", (Mountain View, CA: The Unicode Consortium,
                2009. ISBN 978-1-936213-00-9).
                <http://www.unicode.org/versions/Unicode5.2.0/>.

5.2. Informative References

   [RFC3282]    Alvestrand, H., "Content Language Headers", RFC 3282,
                May 2002.

Authors' Addresses

   Kenneth Whistler
   Sybase, Inc.
   One Sybase Dr.
   Dublin, CA  94568
   USA
   
   Phone: +1 925 236 7429
   EMail: kenw@sybase.com
   
   Glenn Adams
   Skynav (Phil), Inc.
   Lot 14 Boton Area
   Subic Bay Freeport Zone  2222
   Philippines
   
   Phone:
   EMail: glenn@skynav.com
   
   Martin Duerst
   Aoyama Gakuin University
   5-10-1 Fuchinobe
   Sagamihara, Kanagawa  229-8558
   Japan
   
   Phone: +81 42 759 6329
   Fax:   +81 42 759 6495
   EMail: duerst@it.aoyama.ac.jp
   
   Randy Presuhn (editor)
   San Jose, CA  95120
   USA
   
   Phone:
   EMail: randy_presuhn@mindspring.com
   
   John C Klensin
   1770 Massachusetts Ave, Ste 322
   Cambridge, MA  02140
   USA
   
   Phone: +1 617 245 1457
   EMail: john+ietf@jck.com