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MULTILINGUAL DOMAIN NAMES

Hirofumi Hotta

hotta@jprs.jp

JOINT ITU/WIPO SYMPOSIUM

December 6, 2001

http:// 日本レジストリサービス .jp

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ASCII characters in the Internet

• The Internet as the birth– Born in the United States– Research and academic users

• Limited resources in computers and communication devices– Only ASCII codes are used for the core of the Internet

Only ASCII characters have been usedeven by people using non-ASCII characters in social life

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Ex) non-English characters in e-mail

• Step1– Phonetic mapping in e-mail texts

• Step2– Native language characters in e-mail texts

• Step3– Native language characters in “Subject” fields

• Step4 ?– Native language characters in “To” and “From” field

• Names such as company names and personal names in the social relevant context should be presented in their native language

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What is a domain name ?

• Human readable identifier of an entity within the Internet : Ex) www.itu.int

• Substitute of an IP address

www.itu.int

each label < 63 charactersdomain name < 255 characters

top level domain label

second level domain label

third level domain label

domain name

==

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Domain name structure

“ ”

com

sunyahoo

org jp

co or go

uk au

ad

jprs

int

itu wipo

nic

WWW

WWW

.. ..

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Characters in domain names

• Consumers

• ASCII character set users– Natively ex) English

– In transliterated form ex) Malay

• Non-ASCII character set users– Chinese, Japanese, Korean, Arabic, Tamil, ….

LDHComputer Engineers

Wider users ???

(letters-digits-hyphen)

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Demands on multilingual domain names

• Rapid growth of the Internet– More non-English speakers are becoming Internet users

• People using non-ASCII characters• Undesirable unification in LDH world– 博文 , 博史 , 宏史 , …..are all “hirofumi”s in ASCII space– Apostrophe, accents, umlauts, ….. cannot be used in ASCII space

Demand on multilingual domain names

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History (technology)

• Late 1990s– Multilingual domain names were developed at the Nati

onal University of Singapore

• July 1998– Asia Pacific Networking Group

• iDNS Working group : development of the experimental implementation of an Internationalized multilingual multiscript Domain Names Service– Why shouldn’t domain names be internationalized too, now that

the Internet has grown to reach almost every corner of the world using different languages?

• iDomain Working Group : creation of an iDNS testbed in Asia Pacific countries

• China, Japan, Korea, Hong Kong, Singapore, Taiwan, Thailand, ….

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History (technology) - continued

• 1998-1999– Prototypes demonstrated in international conferences– BoFs held in international conferences

• APRICOT• INET

– Singapore, China, Hong Kong, Korea, Japan, … expressed interests in implementation

• Nov. 1999– BoF in IETF– IETF Mailing list discussion

• Jan. 2000 -– IDN (Internationalized Domain Name) Working Grou

p in IETF

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History (deployment)

• End of 1999– Several companies began commercialization of the mu

ltilingual domain name technology– Several testbeds emerged

• July 2000 - – MINC (Multilingual Domain Names Consortium)

• promotion of the multilingualization of Internet names, including Internet domain names and keywords, the internationalization of Internet names standards and protocols, technical coordination, and liaison with other international bodies

– Country/regional organizations• AINC (Arabic Internet Names Consortium)• CDNC (Chinese Domain Name Consortium )• INFITT (International Forum for IT in Tamil )• JDNA (Japanese Domain Names Association )

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History (policy)

• March 2001– Internationalized Domain Name (IDN) Working Group in

ICANN Board• Fact finding survey concerning technical, policy, and service aspec

ts• Survey report published in Sept. 2001

– Market demand shown– List of issues elaborated

– GAC (Governmental Advisory Committee) of ICANN• communiqué expressing GAC’s support for multilingual domain

names– With regard to international domain names, the GAC confirms the i

mportance and interests of this development to the benefit of Internet users worldwide

• Sept. 2001– IDN Committee

• Will recommend solutions of non-technical issues

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How domain names are resolved

IP address of .com name serverIP address of .int name serverIP address of .jp name server :

IP address of itu.int name serverIP address of wipo.int name server :

root server

.int name server

IP address of www.itu.intIP address of intra.itu.int ：

A server having www.itu.int

itu.int name server

intend to browse http://www.itu.int

managed by IANA

managed by ITU

managed by IANAon behalf of .int

http port

Internet

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156.106.192.32

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Where multilingual domain names are recognized

DNS

serverapplicationclient

applicationuser

Internet

currently ASCII domain names

ASCII domain names

multilingual domain names

application

multilingual domain namesoption 1

option 2

in the future

PC

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Key technical questions

• How should non-ASCII codes be represented ? <Q1>• Where should non-ASCII codes be recognized ? <Q2>– in the client application / in the DNS server

• What is the technical mechanism that maps multilingual domain names to current DNS technology ? <Q3>

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Basic technical requirements

• Preservation of compatibility with current domain names

• Preservation of uniqueness of domain name space

• The Internet must not be divided into islands

Required by IAB (Internet Architecture Board)

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Character codes of multilingual domain names

• Current : proprietary (local) standard– in PCs– in PDAs– in Internet-enabled phones

• Best current solution may be– UNICODE – Specification of code sets of many languages

• Additional issues– traditional Chinese characters / simplified Chinese ch

aracters• Are they same characters in domain names ?• Is this a local code issue or universal protocol issue ?

<Q1>

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Client-side vs. Server-side solutions

• Client-side solution– Translation between multilingual script and ASCII-

compatible representation is performed in the user application

– Domain names are processed as ASCII domain names all over the Internet

• Server-side solution– Domain names are sent over the Internet in local

encoding– Applications and services communicate with each

other using non-ASCII domain names all the way

ASCII domain names

multilingual domain names

multilingual domain namesclient-sidesolution

server-sidesolution

user application DNS

<Q2>

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Client-side solution > Server-side solution

• IETF is moving towards client-side solution

• Stability– DNS is a huge distributed database– DNS is working on a delicate balance– Substantial change of DNS is dangerous

• Deployment speed– Changing all the servers takes long time

• Consistency– Partial deployment of server-side solution may lead to separat

ion of the Internet

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How multilingual string is converted to ASCII

original string

normalizedstring

ASCIIstring

Internet(based on ASCII)

unification of the strings considered to be the same

conversion to an ASCII string

NAMEPREP

ACE

ABC カンパニー .JPＡＢＣｶﾝﾊﾟﾆｰ .JPＡ B Ｃカンハ゜ニー .JP

ABC カンパニー .JP

BQ--GD7UD72C75B2X46RZP6A.JP

ex)

ex)

ex)

<Q3>

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NAMEPREP and ACE

• NAMEPREP (Preparation of Internationalized Host Names)– Multilingual string representations which should be regarded as the same string

are converted into one representation• Case fold• Normalize• Prohibit

• ACE (ASCII Compatible Encoding)– Multilingual representation is converted into an appropriate ASCII domain name– Ex) ACE algorithm

• RACE– BQ--3BS6KZZMRKPDBSJQ4EYKIMHTKQGU7CY

• AMC-ACE-Z– ZQ--ECKWD4C7CU47R2WFQW7A0ECL32K

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Issues in using ACE

• Subspace is used by multilingual domain names

• Issues– Reservation of the subspace– Length limitation is severer

• Domain label• Domain name

ASCII Domain Names

ACE-ed Multilingual Domain Names

Multilingual Domain Names

ACE

decode

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IDNA

user

internalrepresentation

UI

API

application servers

end system

application

local

international

resolver

DNS servers

NAMEPREPTo/From Unicode

To/From ACE

NAMEPREP

to/from ACE

to/from Unicode

(Internationalizing Host Names in Applications)

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Impact on the DNS structure

• Alternate root

Hierarchy overseen

by ICANN

multilingual domain name

space

multilingual domain name

space

NameServer

NameServer

NameServer

TLDs not authorized by ICANN

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authoritative root

multilingualized

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Impact on the DNS structure (continued)

• Inclusive root (variation of alternate root)

Hierarchy overseen

by ICANN

multilingual domain name

space

NameServer

unauthorized TLDs can be seen together with ICANN’s

multilingualized

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Impact on the DNS structure (continued)

• Pseudo-root (zero level domain)

multilingual domain name

space

NameServer

Hierarchy overseen by ICANN

銀行 . 企業 .jp

append “.jp” to “ 銀行 . 企業”

jp

企業

銀行

銀行 . 企業

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Defining a multilingual top level domain

• Current implementation of multilingual domain names– Second level domain or under

• Allowed by current DNS architecture and technology

– Top level domain• Alternate root• Inclusive root• Pseudo-root

• Above are only to satisfy commercial drive or users’ demands on early deployment of multilingual domain names

• It is important for ICANN to define a multilingual top level domain creation policy

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Issues in various TLDs• {non-ASCII-string}.{ASCII-ccTLD}• {non-ASCII-string}.{ASCII-gTLD}– Organizations already being authorized are responsible for the domain name space

• {any-string}.{non-ASCII-ccTLD}– One organization from the relevant country is named to be responsible for the domain

name space– If a country has more than 1 official language,

• What is the language for non-ASCII-ccTLD, or• How many non-ASCII-ccTLDs are given to the country

• {any-string}.{non-ASCII-gTLD}– No one can tell whether top level domain “. 企業” is Chinese or Japanese– Difficulty in choosing a responsible organization

• who in what country

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Other political issues• What are the languages that constitute multilingual domain names– Some languages have 2 or more kinds of scripts– Traditional Chinese/simplified Chinese

• Who is the language authority for multilingual domain names– Should rules be the same even under different TLDs?

• A single domain name registry should not be the ultimate authority of for the rules• Is such rule definition an international issue?

– Language rules are known to only people using the language• To what extent does the solution need international standard or local coordination?• Each language stakeholders should coordinate among themselves

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Implementations

• VGRS (VeriSign Global Registry Services)• JPNIC/JPRS (Japan Network Information Center / Japan Registry

Service)• i-DNS.net• CNNIC (China Internet Network Information Center)• Walid• Neteka• NativeNames

::

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Future Issues

synergydeployment of name servers

with multilingualdomain names

growth of the number of multilingualdomain names and their users

applications with

multilingualdomain name

facilities

policy and coordination of registration and management rules

technology standardization and development

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