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
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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.
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.
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.
[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/>.