Network Working Group P. Faltstrom, Ed. Internet-Draft Cisco Intended status: Standards Track October 18, 2010 Expires: April 21, 2011 The Unicode code points and IDNA - Unicode 6.0 draft-faltstrom-5892bis-00.txt Abstract This document specifies updates Section 2.7 of RFC 5892 so that the calculation of the rules are backward compatible when Unicode 6.0 is released. Status of this Memo This Internet-Draft is submitted in full conformance with the provisions of BCP 78 and BCP 79. Internet-Drafts are working documents of the Internet Engineering Task Force (IETF). Note that other groups may also distribute working documents as Internet-Drafts. The list of current Internet- Drafts is at http://datatracker.ietf.org/drafts/current/. Internet-Drafts are draft documents valid for a maximum of six 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." This Internet-Draft will expire on April 21, 2011. Copyright Notice Copyright (c) 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. Faltstrom Expires April 21, 2011 [Page 1] Internet-Draft IDNA Codepoints October 2010 Table of Contents 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 2. New section 2.7 . . . . . . . . . . . . . . . . . . . . . . . . 3 2.1. BackwardCompatible (G) . . . . . . . . . . . . . . . . . . 3 3. IANA Considerations . . . . . . . . . . . . . . . . . . . . . . 3 3.1. IDNA derived property value registry . . . . . . . . . . . 3 4. Security Considerations . . . . . . . . . . . . . . . . . . . . 4 5. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 4 6. References . . . . . . . . . . . . . . . . . . . . . . . . . . 4 6.1. Normative References . . . . . . . . . . . . . . . . . . . 4 6.2. Informative References . . . . . . . . . . . . . . . . . . 4 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . . 4 Faltstrom Expires April 21, 2011 [Page 2] Internet-Draft IDNA Codepoints October 2010 1. Introduction RFC 5892 [RFC5892] specifies an algorithm that based on The Unicode Standard [Unicode6] defines a derived property value. Unicode 6.0 have one codepoint that has changed GeneralCategory which implies the codepoint would move from PVALID to DISALLOWED. This document updates section 2.7 Backward Compatible and adds the codepoint U+19DA NEW TAI LUE THAM DIGIT ONE to it. 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 [RFC2119]. 2. New section 2.7 Between Unicode 5.2 and 6.0, three codepoints have changed in a non- compatible way. U+0CF1 and U+0CF2 move from DISALLOWED to PVALID, and can be treated as codepoints that move from UNASSIGNED to PVALID. U+19DA moves from PVALID to DISALLOWED due to a change of GeneralCategory from Nd to No. This new section 2.7 has added U+19DA for backward compatibility reasons. 2.1. BackwardCompatible (G) G: cp is in {19DA} This category includes the code points that property values in versions of Unicode after 5.2 have changed in such a way that the derived property value would no longer be PVALID or DISALLOWED. If changes are made to future versions of Unicode so that code points might change property value from PVALID or DISALLOWED, then this table can be updated and keep special exception values so that the property values for code points stay stable. PVALID -- Would otherwise have been DISALLOWED 19DA; PVALID # NEW TAI LUE THAM DIGIT ONE 3. IANA Considerations 3.1. IDNA derived property value registry IANA is to update the algorithm used for derived property value registry to reflect this change in the algorithm. Faltstrom Expires April 21, 2011 [Page 3] Internet-Draft IDNA Codepoints October 2010 4. Security Considerations If algorithm presented in RFC 5892 [RFC5892] is applied to Unicode 6.0 without adding the change described in this document, the codepoint U+19DA will have the wrong derived property value. That in turn will make the codepoint DISALLOWED instead of PVALID. 5. Acknowledgements The main contributors are (in alphabetical order) Eric Brunner- Williams, Vint Cerf, Tina Dam, Mark Davis, Paul Hoffman, John Klensin, Pete Resnick, Markus Scherer, Andrew Sullivan, Kenneth Whistler and Nicholas Williams. 6. References 6.1. Normative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC5892] Faltstrom, P., "The Unicode Code Points and Internationalized Domain Names for Applications (IDNA)", RFC 5892, August 2010. [Unicode6] The Unicode Consortium, "The Unicode Standard, Version 6.0.0", 2010. 6.2. Informative References Author's Address Patrik Faltstrom (editor) Cisco Email: paf@cisco.com Faltstrom Expires April 21, 2011 [Page 4]