The Unicode Code Points and Internationalized Domain Names for Applications (IDNA) - Unicode 6.0

Internet Engineering Task Force (IETF)                 P. Faltstrom, Ed.
Request for Comments: 6452                                         Cisco
Category: Standards Track                                P. Hoffman, Ed.
ISSN: 2070-1721                                           VPN Consortium
                                                           November 2011


                      The Unicode Code Points and
  Internationalized Domain Names for Applications (IDNA) - Unicode 6.0

Abstract

   This memo documents IETF consensus for Internationalized Domain Names
   for Applications (IDNA) derived character properties related to the
   three code points, existing in Unicode 5.2, that changed property
   values when version 6.0 was released.  The consensus is that no
   update is needed to RFC 5892 based on the changes made in Unicode
   6.0.

Status of This Memo

   This is an Internet Standards Track document.

   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).  Further information on
   Internet Standards is available in 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/rfc6452.

Copyright Notice

   Copyright (c) 2011 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
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   described in the Simplified BSD License.

Table of Contents

   1. Introduction ....................................................2
      1.1. U+0CF1 KANNADA SIGN JIHVAMULIYA ............................2
      1.2. U+0CF2 KANNADA SIGN UPADHMANIYA ............................2
      1.3. U+19DA NEW TAI LUE THAM DIGIT ONE ..........................2
   2. IETF Consensus ..................................................2
   3. IANA Considerations .............................................3
   4. Security Considerations .........................................3
   5. Acknowledgements ................................................3
   6. Normative References ............................................3

1.  Introduction

   RFC 5892 [RFC5892] specifies an algorithm that was defined when
   version 5.0 (later updated to version 5.2) [Unicode5.2] was the
   current version of Unicode, and it also defines a derived property
   value based on that algorithm.  Unicode 6.0 [Unicode6] has changed
   GeneralCategory of three code points that were allocated in
   Unicode 5.2 or earlier.  This implies that the derived property value
   differs depending on whether the property definitions used are from
   Unicode 5.2 or 6.0.  These are non-backward-compatible changes as
   described in Section 5.1 of RFC 5892.

   The three code points are:

1.1.  U+0CF1 KANNADA SIGN JIHVAMULIYA

   The GeneralCategory for this character changes from So to Lo.  This
   implies that the derived property value changes from DISALLOWED to
   PVALID.

1.2.  U+0CF2 KANNADA SIGN UPADHMANIYA

   The GeneralCategory for this character changes from So to Lo.  This
   implies that the derived property value changes from DISALLOWED to
   PVALID.

1.3.  U+19DA NEW TAI LUE THAM DIGIT ONE

   The GeneralCategory for this character changes from Nd to No.  This
   implies that the derived property value changes from PVALID to
   DISALLOWED.

2.  IETF Consensus

   No change to RFC 5892 is needed based on the changes made in
   Unicode 6.0.

   This consensus does not imply that no changes will be made to
   RFC 5892 for all future updates of The Unicode Standard.

   This RFC has been produced because 6.0 is the first version of
   Unicode to be released since IDNA2008 was published.

3.  IANA Considerations

   IANA has updated the derived property value registry according to
   RFC 5892 and the property values defined in The Unicode Standard
   version 6.0.

4.  Security Considerations

   When the algorithm presented in RFC 5892 is applied using the
   property definitions of Unicode Standard version 6.0, the result will
   be different from when it is applied using the property definitions
   of Unicode 5.2 for the three code points discussed in this document.
   The three code points are unlikely to occur in internationalized
   domain names, however, so the security implications of the changes
   are minor.

5.  Acknowledgements

   The main contributors are (in alphabetical order) Eric Brunner-
   Williams, Vint Cerf, Tina Dam, Mark Davis, Martin Duerst, John
   Klensin, Pete Resnick, Markus Scherer, Andrew Sullivan, Kenneth
   Whistler, and Nicholas Williams.

   Not all contributors believe that the solution for the issues
   discussed in this document is optimal.

6.  Normative References

   [RFC5892]     Faltstrom, P., Ed., "The Unicode Code Points and
                 Internationalized Domain Names for Applications
                 (IDNA)", RFC 5892, August 2010.

   [Unicode5.2]  The Unicode Consortium, "The Unicode Standard,
                 Version 5.2.0", Unicode 5.0.0, Boston, MA,
                 Addison-Wesley ISBN 0-321-48091-0, as amended
                 by Unicode 5.2.0, October 2009,
                 <http://www.unicode.org/versions/Unicode5.2.0/>.

   [Unicode6]    The Unicode Consortium, "The Unicode Standard,
                 Version 6.0.0", October 2010,
                 <http://www.unicode.org/versions/Unicode6.0.0/>.

Authors' Addresses

   Patrik Faltstrom (editor)
   Cisco

   EMail: paf@cisco.com


   Paul Hoffman (editor)
   VPN Consortium

   EMail: paul.hoffman@vpnc.org