Network Working Group                                        S. Sharikov
Internet-Draft                                               Regtime Ltd
Intended status: Informational                             D. Miloshevic
Expires: May 13, 2010                                            Afilias
                                                              J. Klensin
                                                        November 9, 2009


     Internationalized Domain Names Registration and Administration
            Guideline for European languages using Cyrillic
                     draft-sharikov-idn-reg-02.txt

Abstract

   This document is a guideline for Registries and Registrars on
   registering internationalized domain names (IDNs) based on (in
   alphabetical order) Bosnian, Bulgarian, Byelorussian, Kildin Sami,
   Macedonian, Montenegrin, Russian, Serbian, and Ukrainian languages in
   a DNS zone.  For completeness of the "European" languages, it also
   discusses the additional characters needed for Moldovan when it is
   written in Cyrillic script.  It describes appropriate characters for
   registration and variant considerations for characters from Greek and
   Latin scripts with similar appearances and/or derivations.

Status of this Memo

   This Internet-Draft is submitted to IETF in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF), its areas, and its working groups.  Note that
   other groups may also distribute working documents as Internet-
   Drafts.

   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."

   The list of current Internet-Drafts can be accessed at
   http://www.ietf.org/ietf/1id-abstracts.txt.

   The list of Internet-Draft Shadow Directories can be accessed at
   http://www.ietf.org/shadow.html.

   This Internet-Draft will expire on May 13, 2010.

Copyright Notice



Sharikov, et al.          Expires May 13, 2010                  [Page 1]


Internet-Draft                Cyrillic IDNs                November 2009


   Copyright (c) 2009 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 BSD License.

   This document may contain material from IETF Documents or IETF
   Contributions published or made publicly available before November
   10, 2008.  The person(s) controlling the copyright in some of this
   material may not have granted the IETF Trust the right to allow
   modifications of such material outside the IETF Standards Process.
   Without obtaining an adequate license from the person(s) controlling
   the copyright in such materials, this document may not be modified
   outside the IETF Standards Process, and derivative works of it may
   not be created outside the IETF Standards Process, except to format
   it for publication as an RFC or to translate it into languages other
   than English.



























Sharikov, et al.          Expires May 13, 2010                  [Page 2]


Internet-Draft                Cyrillic IDNs                November 2009


Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
     1.1.  Similar Characters and Variants  . . . . . . . . . . . . .  4
     1.2.  Terminology  . . . . . . . . . . . . . . . . . . . . . . .  4
   2.  Languages and Characters . . . . . . . . . . . . . . . . . . .  5
     2.1.  Bosnian and Serbian  . . . . . . . . . . . . . . . . . . .  5
     2.2.  Bulgarian  . . . . . . . . . . . . . . . . . . . . . . . .  5
     2.3.  Byelorussian . . . . . . . . . . . . . . . . . . . . . . .  5
     2.4.  Kildin Sami  . . . . . . . . . . . . . . . . . . . . . . .  6
     2.5.  Macedonian . . . . . . . . . . . . . . . . . . . . . . . .  6
     2.6.  Moldovan . . . . . . . . . . . . . . . . . . . . . . . . .  6
     2.7.  Montenegrin  . . . . . . . . . . . . . . . . . . . . . . .  6
     2.8.  Russian  . . . . . . . . . . . . . . . . . . . . . . . . .  7
     2.10. Ukrainian  . . . . . . . . . . . . . . . . . . . . . . . .  7
   3.  Language-based Tables  . . . . . . . . . . . . . . . . . . . .  7
   4.  Table processing rules . . . . . . . . . . . . . . . . . . . .  7
   5.  Table Format . . . . . . . . . . . . . . . . . . . . . . . . .  7
   6.  Steps after registering an input label . . . . . . . . . . . .  8
   7.  Acknowledgments  . . . . . . . . . . . . . . . . . . . . . . .  8
   Appendix A.  European Cyrillic Character Tables  . . . . . . . . .  9
   8.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 14
     8.1.  Normative References . . . . . . . . . . . . . . . . . . . 14
     8.2.  Informative References . . . . . . . . . . . . . . . . . . 15
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 15


























Sharikov, et al.          Expires May 13, 2010                  [Page 3]


Internet-Draft                Cyrillic IDNs                November 2009


1.  Introduction

   Cyrillic is one of a fairly small number of scripts that are used,
   with different subsets of characters, to write a large number of
   languages, some of which are not closely related to the others.  When
   those languages might be used together in a zone (typical of generic
   TLDs (gTLDs) but likely in other zones both at and below the root,
   special considerations for intermixing characters may apply.
   Cyrillic also has the property that, while it is usually considered a
   separate script from the Latin (Roman) and Greek ones, it shares many
   characters with them, creating opportunities for visual confusion.

   This specification provides guidelines for the use of Cyrillic, as
   encoded in Unicode [Unicode51] with internationalized domain name
   (IDN) labels derived from most "European" languages that use the
   script (use of the term "European" is a convenience, since there is
   disagreement about the relevant boundaries for different purposes
   and, of course, much of Russia lies within geological Asia).
   Specifically it covers (in alphabetic order) Bosnian, Bulgarian,
   Byelorussian, the Kildin member of the Sami (often written "Saami")
   language family, Macedonian, Montenegrin, Russian, Serbian, and
   Ukrainian.  Supplemental tables, based on information in the Unicode
   Standard and a recently-issued Montenegrin government standard
   [MontenegrinChars] are provided for use with Montenegrin.  Moldovan
   is no longer in official use with Cyrillic script and no
   registrations are considered likely in Cyrillic, at least within the
   relevant ccTLD.  Languages of Asia that use Cyrillic are not
   considered here and should be the subject of separate specifications.

   While Cyrillic script is the primary one used for many of the
   relevant languages and countries, Latin script is often used instead
   of, or in combination with, it.  Standard keyboards used in most of
   the countries have both Cyrillic and Latin characters.  Therefore
   some registries could use Latin scripts for domain names registration
   in their zones.  In some cases, there would even be a requirement for
   mixing Cyrillic and Latin characters in the same label although this
   is not generally considered desirable.  In addition, registries that
   support many scripts will probably encounter the need to support
   labels in Greek or Latin scripts as well as Cyrillic and a large
   number of character forms are shared among those three scripts.

   Because the DNS has no way for the end-user to distinguish among the
   languages that might have been used to inspire a particular label, it
   seems useful to treat the characters of a large number of languages
   that use Cyrillic in their writing systems together, rather than
   trying to differentiate them.  The discussion and tables in this
   specification should provide a foundation for developing more
   restrictive rules for zones in which only a single language is likely



Sharikov, et al.          Expires May 13, 2010                  [Page 4]


Internet-Draft                Cyrillic IDNs                November 2009


   to be used, but it does not specify those language-specific rules.

1.1.  Similar Characters and Variants

   For some human languages, there are characters and/or strings that
   have equivalent or near-equivalent meanings.  If someone is allowed
   to register a name with such a character or string, the registry
   might want to automatically register all the names that have the same
   meaning in that language.  Further, some registries might want to
   restrict the set of characters to be registered for language-based
   reasons.  In addition, IDNA [RFC3490] allows the use of thousands of
   non-alphanumeric characters, and some zone administrators will want
   to prohibit some or all of these characters.

   So-called "variant techniques", introduced in [RFC3743] and
   generalized beyond East Asian language in [RFC4290], describe ways of
   registering IDN domain names to decrease the risk of
   misunderstandings, cybersquatting, and other forms of confusion.

   The tables below (Appendix A) identify confusable characters in Latin
   and Greek scripts that might be easily confused with Cyrillic ones.

1.2.  Terminology

   The terminology that follows is derived from [RFC3743] and [RFC4290],
   but this specification does not depend on them.

   A "string" is an ordered set of one or more characters.

   This document discusses characters that have equivalent or near-
   equivalent characters or strings.  The "base character" is the
   character that has one or more equivalents; the "variant(s)" are the
   character(s) and/or string(s) that are equivalent to the base
   character.

   A "registration bundle" is the set of all labels that comes from
   expanding all base characters for a single name into their variants.

   A registry is the administrative authority for a DNS zone.  That is,
   the registry is the body that makes and enforces policies that are
   used in a particular zone in the DNS.  The term "registry" applies to
   all zones in the DNS, not only those that exist at the top level.

   [[anchor4: Note in Draft: This specification is based on the original
   version of IDNA.  Updates to any revision should be obvious, but the
   terminology should be adjusted in needed and special attention should
   be paid to the mapping-only variants listed in the Appendix.  (RFC
   Editor, if the I-D reaches you with this note in place, please just



Sharikov, et al.          Expires May 13, 2010                  [Page 5]


Internet-Draft                Cyrillic IDNs                November 2009


   drop it.)]]


2.  Languages and Characters

   In the interest of clarity and balance, this document describes a
   "Base Cyrillic" set of twenty-three characters for use in comparing
   the character usage for Russian and Central European languages that
   use Cyrillic.  The balance of this section compares the character
   usage of the individual languages in that group.

   "Base Cyrillic" consists of the following Unicode code points (names
   associated with these code points and those below appear in
   Appendix A): U+0430, U+0431, U+0432, U+0433, U+0434, U+0435, U+0436,
   U+0437, U+043A, U+043B, U+043C, U+043D, U+043E, U+043F, U+0440,
   U+0441, U+0442, U+0443, U+0444, U+0445, U+0446, U+0447, U+0448.

   In addition, modern writing systems that use Cyrillic do not have
   digits separate from the "European" ones used with Latin characters.
   For registries that permit digits to appear in domain name labels,
   the "Base Cyrillic" code point listed above should be considered to
   include U+0030, U+0031, U+0032, U+0033, U+0034, U+0035, U+0036,
   U+0037, U+0038, and U+0039 (Digit Zero, and Digit One, through Digit
   Nine).  The Hyphen-Minus character (U+0029) may also be used.

   The individual languages that are the focus of this specification are
   discussed below (in English alphabetical order):

2.1.  Bosnian and Serbian

   Bosnian and Serbian have 30 letters in the alphabet and the
   additional seven characters to the base of 23 shared Cyrillic
   characters: U+0438, U+0458, U+0452, U+0459, U+045A, U+045B, U+045F.

2.2.  Bulgarian

   The Bulgarian alphabet has thirty characters, seven in addition to
   the basic twenty-three: U+0456, U+0439, U+0449, U+044A, U+044C,
   U+044E, U+044F.

2.3.  Byelorussian

   Byerlorussian alphabet has 32 characters, i.e., nine characters in
   addition to the base of 23 characters: U+0451, U+0456, U+0439,
   U+044B, U+044C, U+045E, U+044D, U+044E, U+044F.






Sharikov, et al.          Expires May 13, 2010                  [Page 6]


Internet-Draft                Cyrillic IDNs                November 2009


2.4.  Kildin Sami

   According to the best information available (see [Riessl07] and the
   references he cites), the Kildin Sami orthography has __ characters,
   __ in addition to the basic set.  Many of these characters have no
   precomposed forms in Unicode and hence must be written with combining
   characters.  The characters are: U+0430 U+0304*, U+0435 U+0304*,
   U+0438, U+0439, U+043E U+0304, U+044A, U+044B, U+044B U+0304, U+044C,
   U+044D, U+044D U+0304, U+044E, U+044E U+0304, U+044F, U+044F U+0304,
   U+0451, U+0451 U+0304, U+0458, U+048B, U+048D, U+048F, U+04BB,
   U+04C6, U+04C8, U+04CA, U+04CE, U+04D3, U+04E3, U+04E7, U+04ED,
   U+04EF, U+04F1, U+04F9.

   *  These characters, CYRILLIC SMALL LETTER A with a COMBINING MACRON
      and CYRILLIC SMALL LETTER IE with a COMBINING MACRON,
      respectively, have the same visual appearance as LATIN SMALL
      LETTER A WITH MACRON (U+0101) and LATIN SMALL LETTER E WITH MACRON
      (U+0113).  The latter character is specified by some sources
      including Riessler [Riessl07] (the former doesn't appear to be,
      but is obvious).  However, U+0101 and U+0113 are Latin Script
      characters so, if either is used, any tests on homogeneity of the
      script within a label need to be made with care.  If some input
      systems produce U+0113 (or U+0101) and others produce the two-
      character combining sequence, a variant approach may be
      appropriate.

      Similar issues may apply to other Kildin Sami characters
      constructed with combining sequences.

2.5.  Macedonian

   Macedonian has 31 characters in the alphabet.  This is eight in
   addition to the basic set: U+0438, U+0458, U+0452, U+0459, U+045A,
   U+045C, U+045F, U+0491, U+0455.

2.6.  Moldovan

   Cyrillic is no longer in everyday use for Moldovan, so no IDN
   registrations are anticipated.

2.7.  Montenegrin

   According to the most recent government specification
   [MontenegrinChars], Montenegrin has 32 characters in its alphabet,
   including two that have no precomposed forms in Unicode.  This is
   nine in addition to the basic set and two in addition to Bosnian and
   Serbian: U+0437 U+0302, U+0438, U+0441 U+0302, U+0452, U+0458,
   U+0459, U+045A, U+045B, U+045F.



Sharikov, et al.          Expires May 13, 2010                  [Page 7]


Internet-Draft                Cyrillic IDNs                November 2009


   See Bosnian, Section 2.1, above.

2.8.  Russian

   The current Russian alphabet has 33 characters, consisting of the
   Base Cyrillic set plus an additional ten characters: U+0451 U+0438,
   U+0439, U+0449, U+044A, U+044B, U+044C, U+044D, U+044E, U+044F.

2.9.  Serbian

   See Bosnian, Section 2.1, above.

2.10.  Ukrainian

   Ukrainian has 31 characters and therefore an additional 8 characters
   to the base of 23: U+0454, U+0456, U+0457, U+0491, U+0449, U+044A,
   U+044E, U+044F.


3.  Language-based Tables

   The registration strategy described in this document uses a table
   that lists all characters allowed for input and any variants of those
   characters.  Note that the table lists all characters allowed, not
   only the ones that have variants.


4.  Table processing rules

   The input to the process is called the "input label".  The output of
   the process is either failure (the input label cannot be registered
   at all), or a registration bundle that contains one or more labels
   that have been processed with ToASCII.


5.  Table Format

   The table in Appendix A consists of four columns.  The first and
   second identify the Cyrillic character and the third and fourth
   identify Latin or Greek characters that might be easily confused with
   them visually.  If both a Latin and Greek character are present, the
   Greek one appears in the third and fourth columns on the subsequent
   line (with "..." in the first column to indicate more information
   about the character specified on the previous line).  Variants needed
   only because of case folding are shown with "+++" in the first
   column, as noted in the table.

   Each character in the table is given in the "U+" notation for Unicode



Sharikov, et al.          Expires May 13, 2010                  [Page 8]


Internet-Draft                Cyrillic IDNs                November 2009


   characters followed, in the next column, by its name as shown in the
   Unicode Standard.  For easy reference, the characters are listed in
   the order in which they appear in the Unicode Standard.

   The table does not, and any future revision MUST NOT, have more than
   one entry for a particular base character.


6.  Steps after registering an input label

   A registry has at least three policy options for handling the cases
   where the registration bundle has more than one label.  These
   options, and their key implications, are:

   o  Allocate all labels to the same registrant, making the zone
      information identical to that of the input label.

      This option will cause end users to be able to find names with
      variants more easily, but will result in larger zone files.  In
      principle, the zone file could become so large that it could
      negatively affect the ability of the registry to perform name
      resolution.

   o  Block all labels so they cannot be registered in the future.

      This option does not increase the size of the zone file, but it
      may cause end users to not be able to find names with variants
      that they would expect.

   o  Allocate some labels and block some other labels.

      This option is likely to cause the most confusion with users
      because including some variants will cause a name to be found,
      bout using other variants will cause the name to be not found.

   With any of these three options, the registry MUST keep a database
   that links each label in the registration bundle to the input label.
   This link needs to be maintained so that changes in the non-DNS
   registration information (such as the label's owner name and address)
   is reflected in every member of the registration bundle as well.


7.  Acknowledgments

   Support from Afilias for a major portion of this work is appreciated.

   Cary Karp pointed us to authoritative information on Kildin Sami; his
   help for our being able to treat it the same way other actively-used



Sharikov, et al.          Expires May 13, 2010                  [Page 9]


Internet-Draft                Cyrillic IDNs                November 2009


   European languages that use Cyrillic script is greatly appreciated.


Appendix A.  European Cyrillic Character Tables

   These tables are constructed on the basis of the characters that can
   actually occur in the DNS, i.e., those that can be obtained by
   applying the ToUnicode operation of RFC 3490 to an ACE-encoded label
   as defined there.  If the characters that can be mapped into those
   characters are to be considered instead, then the number of variants
   would increase considerably.  For example, while Cyrillic Small
   Letter A and Greek Small Letter Alpha are readily distinguished
   visually, their capital letter equivalents are not, so, if the
   extended set of Nameprep [RFC3491] mappings are considered, the two
   small letters must be considered variants of each other.

   These additional, possibly-required, variants are shown below with
   "+++" in the first column of the table.

     Characters needed for European languages, other than Moldovan and
                        Sami, written in Cyrillic.

   +----------+--------------------------+---------+-------------------+
   | Cyrillic | Unicode Name             | Variant | Unicode Name      |
   | Char     |                          |         |                   |
   +----------+--------------------------+---------+-------------------+
   | U+0430   | CYRILLIC SMALL LETTER A  | U+0061  | LATIN SMALL       |
   |          |                          |         | LETTER A          |
   | +++      |                          | U+03B0  | GREEK SMALL       |
   |          |                          |         | LETTER ALPHA      |
   | U+0431   | CYRILLIC SMALL LETTER BE |         |                   |
   | U+0432   | CYRILLIC SMALL LETTER VE | U+0062  | LATIN SMALL       |
   |          |                          |         | LETTER V          |
   | +++      |                          | U+03B2  | GREEK SMALL       |
   |          |                          |         | LETTER BETA       |
   | U+0433   | CYRILLIC SMALL LETTER    | U+0072  | LATIN SMALL       |
   |          | GHE                      |         | LETTER R          |
   | +++      |                          | U+03B3  | GREEK SMALL       |
   |          |                          |         | LETTER GAMMA      |
   | U+0434   | CYRILLIC SMALL LETTER DE |         |                   |
   | +++      |                          | U+03B4  | GREEK SMALL       |
   |          |                          |         | LETTER DELTA      |
   | U+0435   | CYRILLIC SMALL LETTER IE | U+0065  | LATIN SMALL       |
   |          |                          |         | LETTER E          |
   | +++      |                          | U+03B5  | GREEK SMALL       |
   |          |                          |         | LETTER EPSILON    |
   | U+0436   | CYRILLIC SMALL LETTER    |         |                   |
   |          | ZHE                      |         |                   |



Sharikov, et al.          Expires May 13, 2010                 [Page 10]


Internet-Draft                Cyrillic IDNs                November 2009


   | U+0437   | CYRILLIC SMALL LETTER ZE |         |                   |
   | U+0438   | CYRILLIC SMALL LETTER I  | U+0075  | LATIN SMALL       |
   |          |                          |         | LETTER U          |
   | U+0439   | CYRILLIC SMALL LETTER    |         |                   |
   |          | SHORT I                  |         |                   |
   | U+043A   | CYRILLIC SMALL LETTER KA | U+006B  | LATIN SMALL       |
   |          |                          |         | LETTER K          |
   | ...      |                          | U+03BA  | GREEK SMALL       |
   |          |                          |         | LETTER KAPPA      |
   | U+043B   | CYRILLIC SMALL LETTER EL |         |                   |
   | +++      |                          | U+039B  | GREEK SMALL       |
   |          |                          |         | LETTER LAMBDA     |
   | U+043C   | CYRILLIC SMALL LETTER EM | U+006D  | LATIN SMALL       |
   |          |                          |         | LETTER M          |
   | +++      |                          | U+03BC  | GREEK SMALL       |
   |          |                          |         | LETTER MU         |
   | U+043D   | CYRILLIC SMALL LETTER EN | U+0068  | LATIN SMALL       |
   |          |                          |         | LETTER H          |
   | +++      |                          | U+03B7  | GREEK SMALL       |
   |          |                          |         | LETTER ETA        |
   | U+043E   | CYRILLIC SMALL LETTER O  | U+006F  | LATIN SMALL       |
   |          |                          |         | LETTER O          |
   | ...      |                          | U+03BF  | GREEK SMALL       |
   |          |                          |         | LETTER OMICRON    |
   | U+043F   | CYRILLIC SMALL LETTER PE | U+006E  | LATIN SMALL       |
   |          |                          |         | LETTER N          |
   | ...      |                          | U+03C0  | GREEK SMALL       |
   |          |                          |         | LETTER PI         |
   | U+0440   | CYRILLIC SMALL LETTER ER | U+0070  | LATIN SMALL       |
   |          |                          |         | LETTER P          |
   | ...      |                          | U+03C1  | GREEK SMALL       |
   |          |                          |         | LETTER RHO        |
   | U+0441   | CYRILLIC SMALL LETTER ES | U+0063  | LATIN SMALL       |
   |          |                          |         | LETTER C          |
   | U+0442   | CYRILLIC SMALL LETTER TE | U+0074  | LATIN SMALL       |
   |          |                          |         | LETTER T          |
   | +++      |                          | U+03C4  | GREEK SMALL       |
   |          |                          |         | LETTER TAU        |
   | U+0443   | CYRILLIC SMALL LETTER U  | U+0079  | LATIN SMALL       |
   |          |                          |         | LETTER Y          |
   | +++      |                          | U+03C5  | GREEK SMALL       |
   |          |                          |         | LETTER UPSILON    |
   | U+0444   | CYRILLIC SMALL LETTER EF | U+03D5  | GREEK PHI SYMBOL  |
   | +++      |                          | U+03C6  | GREEK SMALL       |
   |          |                          |         | LETTER PHI        |
   | U+0445   | CYRILLIC SMALL LETTER HA | U+0078  | LATIN SMALL       |
   |          |                          |         | LETTER X          |




Sharikov, et al.          Expires May 13, 2010                 [Page 11]


Internet-Draft                Cyrillic IDNs                November 2009


   | ...      |                          | U+03C7  | GREEK SMALL       |
   |          |                          |         | LETTER CHI        |
   | U+0446   | CYRILLIC SMALL LETTER    |         |                   |
   |          | TSE                      |         |                   |
   | U+0447   | CYRILLIC SMALL LETTER    |         |                   |
   |          | CHE                      |         |                   |
   | U+0448   | CYRILLIC SMALL LETTER    |         |                   |
   |          | SHA                      |         |                   |
   | U+0449   | CYRILLIC SMALL LETTER    |         |                   |
   |          | SHCHA                    |         |                   |
   | U+044A   | CYRILLIC SMALL LETTER    |         |                   |
   |          | HARD SIGN                |         |                   |
   | U+044B   | CYRILLIC SMALL LETTER    |         |                   |
   |          | YERU                     |         |                   |
   | U+044C   | CYRILLIC SMALL LETTER    |         |                   |
   |          | SOFT SIGN                |         |                   |
   | U+044D   | CYRILLIC SMALL LETTER E  |         |                   |
   | U+044E   | CYRILLIC SMALL LETTER YU |         |                   |
   | U+044F   | CYRILLIC SMALL LETTER YA |         |                   |
   | U+0451   | CYRILLIC SMALL LETTER IO | U+00EB  | LATIN SMALL       |
   |          |                          |         | LETTER E WITH     |
   |          |                          |         | DIAERESIS         |
   | U+0452   | CYRILLIC SMALL LETTER    |         |                   |
   |          | DJE                      |         |                   |
   | U+0453   | CYRILLIC SMALL LETTER    |         |                   |
   |          | GJE                      |         |                   |
   | U+0454   | CYRILLIC SMALL LETTER    | U+03B5  | GREEK SMALL       |
   |          | UKRAINIAN IE             |         | LETTER EPSILON    |
   | U+0455   | CYRILLIC SMALL LETTER    | U+0073  | LATIN SMALL       |
   |          | DZE                      |         | LETTER S          |
   | U+0456   | CYRILLIC SMALL LETTER    | U+0069  | LATIN SMALL       |
   |          | BYELORUSSIAN-UKRAINIAN I |         | LETTER I          |
   | +++      |                          | U+03B9  | GREEK SMALL       |
   |          |                          |         | LETTER IOTA       |
   | U+0457   | CYRILLIC SMALL LETTER    | U+03CA  | GREEK SMALL       |
   |          | UKRAINIAN YI             |         | LETTER IOTA WITH  |
   |          |                          |         | DIALYTIKA         |
   | +++      |                          | U+00EF  | LATIN SMALL       |
   |          |                          |         | LETTER I WITH     |
   |          |                          |         | DIAERESIS         |
   | U+0458   | CYRILLIC SMALL LETTER JE | U+006A  | LATIN SMALL       |
   |          |                          |         | LETTER J          |
   | ...      |                          | U+03F3  | GREEK LETTER YOT  |
   | U+0459   | CYRILLIC SMALL LETTER    |         |                   |
   |          | LJE                      |         |                   |
   | U+045A   | CYRILLIC SMALL LETTER    |         |                   |
   |          | NJE                      |         |                   |




Sharikov, et al.          Expires May 13, 2010                 [Page 12]


Internet-Draft                Cyrillic IDNs                November 2009


   | U+045B   | CYRILLIC SMALL LETTER    |         |                   |
   |          | TSHE                     |         |                   |
   | U+045C   | CYRILLIC SMALL LETTER    |         |                   |
   |          | KJE                      |         |                   |
   | U+045D   | CYRILLIC SMALL LETTER I  |         |                   |
   |          | WITH GRAVE               |         |                   |
   | U+045E   | CYRILLIC SMALL LETTER    |         |                   |
   |          | SHORT U                  |         |                   |
   | U+045F   | CYRILLIC SMALL LETTER    |         |                   |
   |          | DZHE                     |         |                   |
   | U+0491   | CYRILLIC SMALL LETTER    |         |                   |
   |          | GHE WITH UPTURN          |         |                   |
   | U+04C2   | CYRILLIC SMALL LETTER    |         |                   |
   |          | ZHE WITH BREVE           |         |                   |
   +----------+--------------------------+---------+-------------------+

      Additional characters needed for Moldovan written in Cyrillic.

   +--------------+-----------------------------+---------+------------+
   | Cyrillic     | Unicode Name                | Variant | Unicode    |
   | Char         |                             |         | Name       |
   +--------------+-----------------------------+---------+------------+
   | U+04C2       | CYRILLIC SMALL LETTER ZHE   |         |            |
   |              | WITH BREVE                  |         |            |
   | U+0437 +     | Cyrillic Small Letter ZE    |         |            |
   | U+0302       | with Acute                  |         |            |
   | U+0441 +     | Cyrillic Small Letter ES    |         |            |
   | U+0302       | with Acute                  |         |            |
   +--------------+-----------------------------+---------+------------+






















Sharikov, et al.          Expires May 13, 2010                 [Page 13]


Internet-Draft                Cyrillic IDNs                November 2009


     Additional characters needed for Kildin Sami written in Cyrillic.

   +----------+---------------------+----------+-----------------------+
   | Cyrillic | Unicode Name        | Variant  | Unicode Name          |
   | Char     |                     |          |                       |
   +----------+---------------------+----------+-----------------------+
   | U+0430 + | Cyrillic Small      | U+0101   | LATIN SMALL LETTER A  |
   | U+0304   | Letter A with       |          | WITH MACRON           |
   |          | Macron              |          |                       |
   | ...      |                     | U+03B0 + | Greek Small Letter    |
   |          |                     | U+0304   | Alpha with Macron     |
   | U+0435 + | Cyrillic Small      | U+0113   | LATIN SMALL LETTER E  |
   | U+0304   | Letter IE with      |          | WITH MACRON           |
   |          | Macron              |          |                       |
   | U+043E + | Cyrillic Small      | U+014D   | LATIN SMALL LETTER O  |
   | U+0304   | Letter O with       |          | WITH MACRON           |
   |          | Macron              |          |                       |
   | ...      |                     | U+03BF + | Greek Small Letter    |
   |          |                     | U+0304   | Omicron with Macron   |
   | U+044B + | Cyrillic Small      |          |                       |
   | U+0304   | Letter YERU with    |          |                       |
   |          | Macron              |          |                       |
   | U+044D + | Cyrillic Small      |          |                       |
   | U+0304   | Letter E with       |          |                       |
   |          | Macron              |          |                       |
   | U+044E + | Cyrillic Small      |          |                       |
   | U+0304   | Letter YU with      |          |                       |
   |          | Macron              |          |                       |
   | U+044F + | Cyrillic Small      |          |                       |
   | U+0304   | Letter YA with      |          |                       |
   |          | Macron              |          |                       |
   | U+0451 + | Cyrillic Small      | U+00EB + | Latin Small Letter E  |
   | U+0304   | Letter IO with      | U0304    | With Diaeresis and    |
   |          | Macron              |          | Macron                |
   | U+048B   | CYRILLIC SMALL      |          |                       |
   |          | LETTER SHORT I WITH |          |                       |
   |          | TAIL                |          |                       |
   | U+048D   | CYRILLIC SMALL      |          |                       |
   |          | LETTER SEMISOFT     |          |                       |
   |          | SIGN                |          |                       |
   | U+048F   | CYRILLIC SMALL      |          |                       |
   |          | LETTER ER WITH TICK |          |                       |
   | U+04BB   | CYRILLIC SMALL      |          |                       |
   |          | LETTER SHHA         |          |                       |
   | U+04C6   | CYRILLIC SMALL      |          |                       |
   |          | LETTER EL WITH TAIL |          |                       |
   | U+04C8   | CYRILLIC SMALL      |          |                       |
   |          | LETTER EN WITH HOOK |          |                       |



Sharikov, et al.          Expires May 13, 2010                 [Page 14]


Internet-Draft                Cyrillic IDNs                November 2009


   | U+04CA   | CYRILLIC SMALL      |          |                       |
   |          | LETTER EN WITH TAIL |          |                       |
   | U+04CE   | CYRILLIC SMALL      |          |                       |
   |          | LETTER EM WITH TAIL |          |                       |
   | U+04D3   | CYRILLIC SMALL      | U+00E4   | LATIN SMALL LETTER A  |
   |          | LETTER A WITH       |          | WITH DIAERESIS        |
   |          | DIAERESIS           |          |                       |
   | U+04E3   | CYRILLIC SMALL      | U+016B   | LATIN SMALL LETTER U  |
   |          | LETTER I WITH       |          | WITH MACRON           |
   |          | MACRON              |          |                       |
   | U+04E7   | CYRILLIC SMALL      | U+00F6   | LATIN SMALL LETTER O  |
   |          | LETTER O WITH       |          | WITH DIAERESIS        |
   |          | DIAERESIS           |          |                       |
   | U+04ED   | CYRILLIC SMALL      |          |                       |
   |          | LETTER E WITH       |          |                       |
   |          | DIAERESIS           |          |                       |
   | U+04EF   | CYRILLIC SMALL      |          |                       |
   |          | LETTER U WITH       |          |                       |
   |          | MACRON              |          |                       |
   | U+04F1   | CYRILLIC SMALL      |          |                       |
   |          | LETTER U WITH       |          |                       |
   |          | DIAERESIS           |          |                       |
   | U+04F9   | CYRILLIC SMALL      |          |                       |
   |          | LETTER YERU WITH    |          |                       |
   |          | DIAERESIS           |          |                       |
   +----------+---------------------+----------+-----------------------+


8.  References

8.1.  Normative References

   [RFC3490]  Faltstrom, P., Hoffman, P., and A. Costello,
              "Internationalizing Domain Names in Applications (IDNA)",
              RFC 3490, March 2003.

   [RFC3491]  Hoffman, P. and M. Blanchet, "Nameprep: A Stringprep
              Profile for Internationalized Domain Names (IDN)",
              RFC 3491, March 2003.

   [Unicode51]
              The Unicode Consortium, "The Unicode Standard, Version
              5.1.0", 2008.

              Defined by: The Unicode Standard, Version 5.0, Boston, MA,
              Addison-Wesley, 2007, ISBN 0-321-48091-0, as amended by
              Unicode 5.1.0
              (http://www.unicode.org/versions/Unicode5.1.0/).



Sharikov, et al.          Expires May 13, 2010                 [Page 15]


Internet-Draft                Cyrillic IDNs                November 2009


8.2.  Informative References

   [MontenegrinChars]
              Crna Gora Ministarstvo prosvjete i nauke (Ministry of
              Science and Education, Montenegro), "Pravopis Crnogorskoga
              Jezika I", 2009, <http://www.gov.me/files/1248442673.pdf>.

              In Montenegrin, no known English translation.

   [OmniglotSaami]
              Ager, S., "Sami (Saami)", 2009,
              <http://www.omniglot.com/writing/saami.htm>.

   [RFC3743]  Konishi, K., Huang, K., Qian, H., and Y. Ko, "Joint
              Engineering Team (JET) Guidelines for Internationalized
              Domain Names (IDN) Registration and Administration for
              Chinese, Japanese, and Korean", RFC 3743, April 2004.

   [RFC4290]  Klensin, J., "Suggested Practices for Registration of
              Internationalized Domain Names (IDN)", RFC 4290,
              December 2005.

   [Riessl07]
              Riessler, M., "Kola Saami character chart (draft)",
              November 2007.


Authors' Addresses

   Sergey Sharikov
   Regtime Ltd
   Kalinina str.,14
   Samara  443008
   Russia

   Phone: +7(846) 979-9039
   Fax:   +7(846)979-9038
   Email: s.shar@regtime.net













Sharikov, et al.          Expires May 13, 2010                 [Page 16]


Internet-Draft                Cyrillic IDNs                November 2009


   Desiree Miloshevic
   Afilias
   Oxford Internet Institute, 1 St. Giles
   Oxford  OX1 3JS
   United Kingdom

   Phone: +44 7973 987 147
   Email: dmiloshevic@afilias.info


   John C Klensin
   1770 Massachusetts Ave, #322
   Cambridge, MA  02140
   USA

   Phone: +1 617 491 5735
   Email: john-ietf@jck.com


































Sharikov, et al.          Expires May 13, 2010                 [Page 17]