Reference LGR for language: Korean (ko) lgr-second-level-korean-hangul-language-25oct24-en

This document is mechanically formatted from the above XML file for the LGR. It provides additional summary data and explanatory text. The XML file remains the sole normative specification of the LGR.

Date 2024-10-25
LGR Version 3 (Second Level Reference LGR)
Language ko (Korean Language)
Unicode Version 11.0.0

Description

INSTRUCTIONS

  • These instructions cover how to adopt an LGR based on this reference LGR for a given zone and how to prepare the file for deposit in the IANA Repository of IDN Practices.
  • As described the IANA procedure
    (https://www.iana.org/help/idn-repository-procedure)
    an LGR MUST contain the following elements in its header:
    • Script or Language Designator (see below for guidance)
    • Version Number (this must increase with each amendment to the LGR, even if the updates are limited to the header itself)
    • Effective Date (the date at which the policy becomes applicable in operational use)
    • Registry Contact Details (contact name, email address, and/or phone number)
  • The following information is optional:
    • Document creation date
    • Applicable Domain(s)
    • Changes made to the Reference LGR before adopting

Please add or modify the following items in the XML source code for this file before depositing the document in the IANA Repository.
(https://www.iana.org/domains/idn-tables)

Meta Data

Note: version numbers start at 1. RFC 7940 recommends using simple integers. The version comment is optional, please replace or delete the default comment. Version comments may be used by some tools as part of the page header.

<version comment="[Please replace (or delete) the optional comment]">[Please fill in version number, starting at 1]</version>

<date>[Please fill in with publication date, in YYYY-MM-DD format]</date>

<validity-start>[Please fill in effective date, in YYYY-MM-DD format]</validity-start>

Note: the scope element may be repeated, so that the same document can serve for multiple domains.

<scope type="domain">[Please provide, in ".domain" format]</scope>

Registry Contact Information:

Please fill in the Registry Contact Details.

Change History

If you made technical modifications to the LGR, please summarize them in the Change History (and also note the details in the appropriate section of the description).

PLEASE DELETE THESE INSTRUCTIONS BEFORE DEPOSITING THE DOCUMENT

Registry Contact Details

Label Generation Rules for Korean

Overview

This document specifies a set of Label Generation Rules (LGR) for the Korean language using a language-specific repertoire for the second level domain or domains identified above. The format of this file follows [RFC 7940]. This LGR is adapted from the “Reference LGR for the Second Level for the Korean Language” [Ref-LGR-ko-Kore], for details, see Change History below.

Standalone LGR: This LGR is designed to be used in a zone that does not cater to IDNs other than those valid under this LGR. Following existing practice, this LGR also supports ASCII letters and where applicable accounts for any interaction with the remainder of the repertoire.

Repertoire

For the Hangul syllables used to write the Korean language, all references converget on the set of 11,172 Hangul syllables contained in Unicode since version 2.0. These Hangul Syllables are sometimes called Johab, the name originating from the initial standard in which they were defined: KSC C 5601-1992 , and the encoding in which they were represented in that standard. One part of that standard also defines a subset (known as Wansung) which consists of 2,350 Hangul syllables. KSC C5601-1992 later became KS X 1001:2004.

The text in [700] recommends to only use the 2,350 Wansung code points, but given the large deployment of platforms supporting the full Johab repertoire, this recommendation is considered unnecessary in the context of this LGR.

At time of development there was no established practice for the use of Korean ideographs (Hanja) derived from Chinese ideographs (Hanzi) in IDNA labels. Hanja characters are rarely used in Korea (North or South). Therefore it does not seem necessary to add them in a Second Level LGR for Korean Language at this point.

For the second level, the repertoire has been augmented with the ASCII digits, U+0030 0 to U+0039 9; the ASCII lowercase letters, U+0061 a to U+007A z; and U+002D - HYPHEN-MINUS, for a total of 11,209 repertoire elements.

Unlike many other non-Latin Second Level Reference LGRs, the Korean Language LGR includes the basic ASCII Latin letters (a to z) because it is common practice in Korean text to mix Korean and ASCII. Therefore including these letters is not seen as creating added confusability or security risks in the context of a Second Level LGR for the Korean language. It is also supported by current IDNA practice, see [700], for example.

Variants

No variants are applicable when using the LGR in a standalone fashion.

Character Classes

This LGR does not define named character classes.

Rules

Common Rules

By default, the LGR includes the rules and actions to implement the following restrictions mandated by the IDNA protocol. They are marked with ⍟.

  • Hyphen Restrictions — restrictions on the allowable placement of hyphens (no leading/ending hyphen and no hyphen in positions 3 and 4). These restrictions are described in Section 4.2.3.1 of RFC 5891 [150]. They are implemented here as context rule on U+002D (-) HYPHEN-MINUS.
  • Leading Combining Marks — restrictions on the allowable placement of combining marks (no leading combining mark). This rule is described in Section 4.2.3.2 of RFC 5891 [150].

Actions

This LGR includes the default actions for LGRs as well as the action needed to invalidate labels with misplaced combining marks. They are marked with ⍟. For a description see [RFC 7940].

Methodology and Contributors

The LGR in this document has been adapted from the corresponding Reference LGR for the Second Level. The Second Level Reference LGR for the Korean Language was developed by Michel Suignard and Asmus Freytag, verified in expert reviews by Lu Qin and Wil Tan, and based on multiple open public consultations.

Changes from Version Dated 10 October 2016

Language tags have been updated.

Changes from Version Dated 18 May 2021

Unicode Version has been updated.

Changes from Version Dated 25 October 2024

Adopted from the Second Level Reference LGR for the Korean Language [Ref-LGR-ko-Kore] without normative changes.

References

General references for the language:

Other references cited in this document:

[Ref-LGR-ko-Kore]
ICANN, Second Level Reference Label Generation Rules for the Korean Language (ko-Kore), 25 October 2024 (XML)
https://www.icann.org/sites/default/files/packages/lgr/lgr-second-level-korean-hangul-language-25oct24-en.xml
non-normative HTML presentation:
https://www.icann.org/sites/default/files/packages/lgr/lgr-second-level-korean-hangul-language-25oct24-en.html
[RFC 7940]
Davies, K. and A. Freytag, “Representing Label Generation Rulesets Using XML”, RFC 7940, August 2016,
https://www.rfc-editor.org/info/rfc7940
[Unicode 11.0.0]
The Unicode Consortium. The Unicode Standard, Version 11.0.0, (Mountain View, CA: The Unicode Consortium, 2018. ISBN 978-1-936213-19-1)
https://www.unicode.org/versions/Unicode11.0.0/

In the listing of the repertoire by code point, references starting from [0] refer to the version of the Unicode Standard in which the corresponding code point was initially encoded. Other references (starting from [100]) document usage of code points. Entries in the table may have multiple source reference values. In the listing of whole label evaluation and context rules, reference [150] indicates the source for common rules. For more details, see the Table of References below.

Repertoire

Repertoire Summary

Number of elements in repertoire 11209
Number of code points
for each script
Hangul 11172
Latin 26
Common 11
Longest code point sequence 1

Repertoire by Code Point

The following table lists the repertoire by code point (or code point sequence). The data in the Script and Name column are extracted from the Unicode character database. Where a comment in the original LGR is equal to the character name, it has been suppressed.

See also the legend provided below the table.

Code
Point
Glyph Script Name Ref Tags Required Context Comment
U+002D - Common HYPHEN-MINUS [0]   not: hyphen-minus-disallowed  
U+0030 0 Common DIGIT ZERO [0] Common-digit  
U+0031 1 Common DIGIT ONE [0] Common-digit  
U+0032 2 Common DIGIT TWO [0] Common-digit  
U+0033 3 Common DIGIT THREE [0] Common-digit  
U+0034 4 Common DIGIT FOUR [0] Common-digit  
U+0035 5 Common DIGIT FIVE [0] Common-digit  
U+0036 6 Common DIGIT SIX [0] Common-digit  
U+0037 7 Common DIGIT SEVEN [0] Common-digit  
U+0038 8 Common DIGIT EIGHT [0] Common-digit  
U+0039 9 Common DIGIT NINE [0] Common-digit  
U+0061 a Latin LATIN SMALL LETTER A [0], [100], [700]      
U+0062 b Latin LATIN SMALL LETTER B [0], [100], [700]      
U+0063 c Latin LATIN SMALL LETTER C [0], [100], [700]      
U+0064 d Latin LATIN SMALL LETTER D [0], [100], [700]      
U+0065 e Latin LATIN SMALL LETTER E [0], [100], [700]      
U+0066 f Latin LATIN SMALL LETTER F [0], [100], [700]      
U+0067 g Latin LATIN SMALL LETTER G [0], [100], [700]      
U+0068 h Latin LATIN SMALL LETTER H [0], [100], [700]      
U+0069 i Latin LATIN SMALL LETTER I [0], [100], [700]      
U+006A j Latin LATIN SMALL LETTER J [0], [100], [700]      
U+006B k Latin LATIN SMALL LETTER K [0], [100], [700]      
U+006C l Latin LATIN SMALL LETTER L [0], [100], [700]      
U+006D m Latin LATIN SMALL LETTER M [0], [100], [700]      
U+006E n Latin LATIN SMALL LETTER N [0], [100], [700]      
U+006F o Latin LATIN SMALL LETTER O [0], [100], [700]      
U+0070 p Latin LATIN SMALL LETTER P [0], [100], [700]      
U+0071 q Latin LATIN SMALL LETTER Q [0], [100], [700]      
U+0072 r Latin LATIN SMALL LETTER R [0], [100], [700]      
U+0073 s Latin LATIN SMALL LETTER S [0], [100], [700]      
U+0074 t Latin LATIN SMALL LETTER T [0], [100], [700]      
U+0075 u Latin LATIN SMALL LETTER U [0], [100], [700]      
U+0076 v Latin LATIN SMALL LETTER V [0], [100], [700]      
U+0077 w Latin LATIN SMALL LETTER W [0], [100], [700]      
U+0078 x Latin LATIN SMALL LETTER X [0], [100], [700]      
U+0079 y Latin LATIN SMALL LETTER Y [0], [100], [700]      
U+007A z Latin LATIN SMALL LETTER Z [0], [100], [700]      
U+AC00..U+D7A3 [11172] 가..힣 Hangul HANGUL SYLLABLE GA..HANGUL SYLLABLE HIH [1], [100], [110], [401], [700]      

Legend

Code Point
A code point, code point sequence, or code point range. For a range, starting and ending code points are shown separated by ".." and the count is given in "[ ]".
Glyph
The shape displayed depends on the fonts available to your browser.
Script
Shows the script property value from the Unicode Character Database. Combining marks may have the value Inherited and code points used with more than one script may have the value Common. For any code point range, all members have the same script value.
Name
Shows the character or sequence name from the Unicode Character Database. For ranges both the first and last name are shown, if different.
Ref
Links to the references associated with the code point or sequence, if any. For any code point range, all members share the same references.
Tags
LGR-defined tag values. Any tags matching the Unicode script property are suppressed in this view. For any code point range, all members share the same tags.
Required Context
Link to a rule defining the required context a code point or sequence must satisfy. If prefixed by “not:” identifies a context that must not occur.For any code point range, all members share the same required context.
Comment
The comment as given in the XML file. However, if the comment for this row consists only of the code point or sequence name, it is suppressed in this view. By convention, comments starting with “=” denote an alias. If present, the symbol ⍟ marks a default item shared among a set of LGRs.

Variants

This LGR does not specify any variants.

Classes, Rules and Actions

Character Classes

Implicit (except script) 1
Implicit defined by script tag 3

The following table lists all named and implicit classes with their definition and a list of their members intersected with the current repertoire (for larger classes, this list is elided).

Name Definition Count Members or Ranges Ref Comment
implicit Tag=Common-digit 10 {0030-0039}   Any character tagged as Common-digit
implicit Tag=sc:Hang 11172 {AC00-D7A3}   Any character tagged as Hangul
implicit Tag=sc:Latn 26 {0061-007A}   Any character tagged as Latin
implicit Tag=sc:Zyyy 11 {002D 0030-0039}   Any character tagged as Common

Legend

Members or Ranges
Lists the members of the class as code points (xxx) or as ranges of code points (xxx-yyy). Any class too numerous to list in full is elided with "...".
Tag=ttt
A named or implicit class defined by all code points that share the given tag value (ttt).
Implicit
An anonymous class implicitly defined based on tag value and for which there is no named equivalent.

Whole label evaluation and context rules

Number of rules 2
Used to trigger actions 1
Used as context rule (C) 1
Anchored context rules 1

The following table lists all named rules defined in the LGR and indicates whether they are used as trigger in an action or as context (when or not-when) for a code point or variant.

Name Regular Expression Used as
Trigger
Anchor Used as
Context
Ref Comment
leading-combining-mark (start)[∅=[[∅=\p{gc=Mn}] ∪ [∅=\p{gc=Mc}]]]     [150] RFC 5891 restrictions on placement of combining marks ⍟
hyphen-minus-disallowed ((((start))← ⚓︎)|(⚓︎ →((end)))|(((start)..\u002D)← ⚓︎))   C [150] RFC 5891 restrictions on placement of U+002D - HYPHEN-MINUS ⍟

Legend

Used as Trigger
This rule triggers one of the actions listed below.
Used as Context
This rule defines a required or prohibited context for a code point C or variant V.
Anchor
This rule has a placeholder for the code point for which it is evaluated.
Regular Expression
A regular expression equivalent to the rule, shown in a modified notation as noted:
⚓︎ - context anchor
Placeholder for the actual code point when a context is evaluated. The code point must occur at the position corresponding to the anchor. Rules containing an anchor cannot be used as triggers.
(?<=...) - look-behind
If present encloses required context preceding the anchor.
(?=...) - look-ahead
If present encloses required context following the anchor.
( ) - group
An anonymous nested rule is used to group match operators.
(... | ...) - choice
When there is more than one alternative in a rule, the choices are separated by the alternation operator (...|...).
^ or $ - start or end
^ matches the start of the label; $ matches the end of the label.
. - any code point
. matches any code point.
[\p{ }] - property
Set of all characters matching a given value for a Unicode property [\p{prop=val}]. Note: uppercase “\P” defines the complement of a property set.
[&&, -, ^] - set operators
Sets may be combined by set operators (&& = intersection, - = difference, ^ = symmetric difference) or concatenated (union).
∅= - empty set
Indicates that the following set is empty because of the result of set operations, or because none of its elements is part of the repertoire defined here. A rule with a non-optional empty set never matches.
⍟ - default rule
Rules marked with ⍟ are included by default and may or may not be triggered by any possible label under this LGR.

Actions

The following table lists the actions that are used to assign dispositions to labels and variant labels based on the specified conditions. The order of actions defines their precedence: the first action triggered by a label is the one defining its disposition.

# Condition Rule / Variant Set   Disposition Ref Comment
1 if label matches leading-combining-mark invalid   by default, labels with leading combining marks are invalid
2 if any label (catch-all)   valid   catch all (default action)

Legend

{...} - variant type set
In the “Rule/Variant Set” column, the notation {...} means a set of variant types.

Table of References

The following lists the references cited for specific code points, variants, classes, rules or actions in this LGR. For General references refer to the References section in the Description.

[0] The Unicode Standard, Version 1.1
Any code point originally encoded in Unicode Version 1.1
[1] The Unicode Standard, Version 2.0
Any code point originally encoded in Unicode Version 2.0
[100] Internetstiftelsen i Sverige (IIS), Korean
https://github.com/dotse/IDN-ref-tables/blob/master/language-tables/korean-lang-ref-table.txt
accessed on 2016-10-16
[110] KS X 1001:2004, Code for Information Interchange (Hangueul and Hanja)
[150] RFC 5891, Internationalized Domain Names in Applications (IDNA): Protocol
https://tools.ietf.org/html/rfc5891
[401] The Unicode Consortium, Common Locale Data Repository.- CLDR Version 28 (2015-09-16)- Locale Data Summary for Korean [ko]-
https://www.unicode.org/cldr/charts/28/summary/ko.html
Code points cited are from the set of Main Letters
[700] KRNIC (.kr cctld Korean Register)
https://www.iana.org/domains/idn-tables/tables/kr_ko-kr_1.0.html