< draft-faltstrom-unicode11-06.txt		draft-faltstrom-unicode11-07.txt >
	Network Working Group P. Faltstrom		Network Working Group P. Faltstrom
	Internet-Draft Netnod		Internet-Draft Netnod
	Intended status: Standards Track December 09, 2018		Intended status: Standards Track January 07, 2019
	Expires: June 12, 2019		Expires: July 11, 2019
	IDNA2008 and Unicode 11.0.0		IDNA2008 and Unicode 11.0.0
	draft-faltstrom-unicode11-06		draft-faltstrom-unicode11-07
	Abstract		Abstract
	This document describes the changes between Unicode 6.3.0 and Unicode		This document describes the changes between Unicode 6.3.0 and Unicode
	11.0.0 in the context of IDNA2008. It further suggests a path		11.0.0 in the context of IDNA2008. It further suggests a path
	forward for the IETF to ensure IDNA2008 follows the evolution of the		forward for the IETF to ensure IDNA2008 follows the evolution of the
	Unicode Standard.		Unicode Standard.
	Some changes have been made in the Unicode Standard related to the		Some changes have been made in the Unicode Standard related to the
	algorithm IDNA2008 specifies. IDNA2008 allows adding exceptions to		algorithm IDNA2008 specifies. IDNA2008 allows adding exceptions to
	skipping to change at page 1, line 48 ¶		skipping to change at page 1, line 48 ¶
	Internet-Drafts are working documents of the Internet Engineering		Internet-Drafts are working documents of the Internet Engineering
	Task Force (IETF). Note that other groups may also distribute		Task Force (IETF). Note that other groups may also distribute
	working documents as Internet-Drafts. The list of current Internet-		working documents as Internet-Drafts. The list of current Internet-
	Drafts is at https://datatracker.ietf.org/drafts/current/.		Drafts is at https://datatracker.ietf.org/drafts/current/.
	Internet-Drafts are draft documents valid for a maximum of six months		Internet-Drafts are draft documents valid for a maximum of six months
	and may be updated, replaced, or obsoleted by other documents at any		and may be updated, replaced, or obsoleted by other documents at any
	time. It is inappropriate to use Internet-Drafts as reference		time. It is inappropriate to use Internet-Drafts as reference
	material or to cite them other than as "work in progress."		material or to cite them other than as "work in progress."
	This Internet-Draft will expire on June 12, 2019.		This Internet-Draft will expire on July 11, 2019.
	Copyright Notice		Copyright Notice
	Copyright (c) 2018 IETF Trust and the persons identified as the		Copyright (c) 2019 IETF Trust and the persons identified as the
	document authors. All rights reserved.		document authors. All rights reserved.
	This document is subject to BCP 78 and the IETF Trust's Legal		This document is subject to BCP 78 and the IETF Trust's Legal
	Provisions Relating to IETF Documents		Provisions Relating to IETF Documents
	(https://trustee.ietf.org/license-info) in effect on the date of		(https://trustee.ietf.org/license-info) in effect on the date of
	publication of this document. Please review these documents		publication of this document. Please review these documents
	carefully, as they describe your rights and restrictions with respect		carefully, as they describe your rights and restrictions with respect
	to this document. Code Components extracted from this document must		to this document. Code Components extracted from this document must
	include Simplified BSD License text as described in Section 4.e of		include Simplified BSD License text as described in Section 4.e of
	the Trust Legal Provisions and are provided without warranty as		the Trust Legal Provisions and are provided without warranty as
	skipping to change at page 6, line 7 ¶		skipping to change at page 6, line 7 ¶
	In practice, the Unicode Consortium creates a maximum set of code		In practice, the Unicode Consortium creates a maximum set of code
	points by assigning code points in the Unicode Standard. The		points by assigning code points in the Unicode Standard. The
	IDNA2008 rules based on the Unicode Standard create a subset of these		IDNA2008 rules based on the Unicode Standard create a subset of these
	by assigning the PVALID derived property value to them. DNS		by assigning the PVALID derived property value to them. DNS
	registries and other organizations that deal with IDNs are supposed		registries and other organizations that deal with IDNs are supposed
	to create their own subsets from IDNA2008 for use by those registries		to create their own subsets from IDNA2008 for use by those registries
	and organizations.		and organizations.
	SAC-084 [SAC-084] and RFC 6912 [RFC6912] recommend to DNS registries		SAC-084 [SAC-084] and RFC 6912 [RFC6912] recommend to DNS registries
	and other organizations to be conservative when creating their		and other organizations to be conservative when creating their
	subsets are calculated, and to use the principle of creating subsets		subsets, and to use the principle of creating subsets by inclusion.
	by inclusion.
	4. Notable Changes Between Unicode 6.3.0 and 11.0.0		4. Notable Changes Between Unicode 6.3.0 and 11.0.0
	4.1. Changes in Unicode 7.0.0		4.1. Changes in Unicode 7.0.0
	The character ARABIC LETTER BEH WITH HAMZA ABOVE (U+08A1) was		The character ARABIC LETTER BEH WITH HAMZA ABOVE (U+08A1) was
	introduced in Unicode 7.0.0. This was discussed extensively in the		introduced in Unicode 7.0.0. This was discussed extensively in the
	IETF, and by the IAB in their statement [IAB] requesting the IETF to		IETF, and by the IAB in their statement [IAB] requesting the IETF to
	investigate the issue. Specifically, the IAB stated:		investigate the issue. Specifically, the IAB stated:
	skipping to change at page 6, line 36 ¶		skipping to change at page 6, line 35 ¶
	create "the same" character in multiple ways, the issue with U+08A1		create "the same" character in multiple ways, the issue with U+08A1
	is not unique. The character U+08A1 can be represented with the		is not unique. The character U+08A1 can be represented with the
	sequence ARABIC LETTER BEH (U+0628) and ARABIC HAMZA ABOVE (U+0654).		sequence ARABIC LETTER BEH (U+0628) and ARABIC HAMZA ABOVE (U+0654).
	This identical to LATIN SMALL LETTER A WITH DIAERESIS (U+00E4), that		This identical to LATIN SMALL LETTER A WITH DIAERESIS (U+00E4), that
	can be represented with the sequence LATIN SMALL LETTER A (U+0061)		can be represented with the sequence LATIN SMALL LETTER A (U+0061)
	followed by COMBINING DIAERESIS (U+0308). One difference between		followed by COMBINING DIAERESIS (U+0308). One difference between
	these two sequences is how they are treated in the normalization		these two sequences is how they are treated in the normalization
	forms specified by the Unicode Consortium.		forms specified by the Unicode Consortium.
	U+08A1 is discussed in draft-freytag-troublesome-characters		U+08A1 is discussed in draft-freytag-troublesome-characters
	[I-D.freytag-troublesome-characters] and other Internet Drafts.		[I-D.freytag-troublesome-characters] and other Internet-Drafts.
	Regardless of whether the discussion of those drafts ends in		Regardless of whether the discussion of those drafts ends in
	recommendations to include the code point in the repertoire of		recommendations to include the code point in the repertoire of
	characters permissable for registration or not, it is still		characters permissable for registration or not, it is still
	acceptable to allow the code point to have a derived property value		acceptable to allow the code point to have a derived property value
	of PVALID.		of PVALID.
	4.2. Changes between Unicode 7.0.0 and 10.0.0		4.2. Changes between Unicode 7.0.0 and 10.0.0
	There are no changes made to Unicode between version 7.0.0 and 10.0.0		There are no changes made to Unicode between version 7.0.0 and 10.0.0
	that impact IDNA2008 calculation of the derived property value.		that impact IDNA2008 calculation of the derived property value.
	skipping to change at page 8, line 44 ¶		skipping to change at page 8, line 44 ¶
	others dealing with Internationalized Domain Names) explicitly select		others dealing with Internationalized Domain Names) explicitly select
	appropriate subsets of characters with the derived value of PVALID.		appropriate subsets of characters with the derived value of PVALID.
	Not following these recommendations can lead to various security		Not following these recommendations can lead to various security
	issues. Specifically, allowing confusable characters may lead to		issues. Specifically, allowing confusable characters may lead to
	various phishing attacks, as described in the Security Consideration		various phishing attacks, as described in the Security Consideration
	Sections in the documents listed in section Section 3.1.		Sections in the documents listed in section Section 3.1.
	8. Acknowledgements		8. Acknowledgements
	Thanks to Martin Durst, Asmus Freytag, Ted Hardie, John Klensin, Erik		Thanks to Martin Duerst, Asmus Freytag, Ted Hardie, John Klensin,
	Nordmark, Michel Suignard, Andrew Sullivan and Suzanne Woolf for		Erik Nordmark, Michel Suignard, Andrew Sullivan and Suzanne Woolf for
	input to this document.		input to this document.
	9. References		9. References
	9.1. Normative References		9.1. Normative References
	[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate		[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
	Requirement Levels", BCP 14, RFC 2119,		Requirement Levels", BCP 14, RFC 2119,
	DOI 10.17487/RFC2119, March 1997,		DOI 10.17487/RFC2119, March 1997,
	<https://www.rfc-editor.org/info/rfc2119>.		<https://www.rfc-editor.org/info/rfc2119>.
End of changes. 7 change blocks.
	10 lines changed or deleted		9 lines changed or added
This html diff was produced by rfcdiff 1.48. The latest version is available from http://tools.ietf.org/tools/rfcdiff/