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Interim Paper Cross-Community Working Group on Use of Names of Countries and Territories as Top Level Domains

Open Date: 24 February 2017 Close Date: 21 April 2017 Originating Organization: ccNSO/GNSO, Chartering Organizations Categories/Tags: Policy Development, ccTLDs, Security/Stability, ISO 3166, Top-Level...

Revised Report of the Independent Review of the Trademark Clearinghouse Now Available

LOS ANGELES – 23 February 2017 – The Internet Corporation for Assigned Names and Numbers (ICANN) today published the Revised Report of the Independent Review of the Trademark Clearinghouse. Read the report [PDF, 1.28 MB]. The review was...

Call for Volunteers for the Registration Directory Service (formerly WHOIS) Review Team

DEADLINE EXTENSION – Applications to be appointed to the Registration Directory Service (RDS) Review Team are due on 7 March 2017, 23:59 UTC. ICANN is seeking volunteers to serve on the second review of Registration Directory Service (formerly...

Save the Date: Pre-ICANN58 Policy Open House

Monday, 6 March 2017 10:00 UTC and 19:00 UTC The Policy Development Support Team is pleased to announce two sessions of the Pre-ICANN58 Policy Open House on Monday, 6 March 2017 at 10:00 UTC and 19:00 UTC. The Policy Open House builds on the...




Participación LAC en ICANN57

Conozca más acerca del Programa de becas: Conozca más sobre la GNSO: Conozca más sobre At-Large:...


LAC participation at ICANN57

Learn more about the Fellowship Program: Learn more about the GNSO: Learn more about At-Large: Meet...

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ICANN’s CTO David Conrad Talks About Changing The Master Key Of The DNS

ICANN’s Brad White speaks with David Conrad, ICANN's Chief Technology Officer, about the first root zone key signing key rollover at ICANN57.

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Watch The Wrap - Up Interview With Stephen Crocker And Göran Marby At ICANN57

ICANN's Liana Teo speaks with Board Chair Stephen Crocker and President and CEO Göran Marby about ICANN57.


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Domain Name System
Internationalized Domain Name ,IDN,"IDNs are domain names that include characters used in the local representation of languages that are not written with the twenty-six letters of the basic Latin alphabet ""a-z"". An IDN can contain Latin letters with diacritical marks, as required by many European languages, or may consist of characters from non-Latin scripts such as Arabic or Chinese. Many languages also use other types of digits than the European ""0-9"". The basic Latin alphabet together with the European-Arabic digits are, for the purpose of domain names, termed ""ASCII characters"" (ASCII = American Standard Code for Information Interchange). These are also included in the broader range of ""Unicode characters"" that provides the basis for IDNs. The ""hostname rule"" requires that all domain names of the type under consideration here are stored in the DNS using only the ASCII characters listed above, with the one further addition of the hyphen ""-"". The Unicode form of an IDN therefore requires special encoding before it is entered into the DNS. The following terminology is used when distinguishing between these forms: A domain name consists of a series of ""labels"" (separated by ""dots""). The ASCII form of an IDN label is termed an ""A-label"". All operations defined in the DNS protocol use A-labels exclusively. The Unicode form, which a user expects to be displayed, is termed a ""U-label"". The difference may be illustrated with the Hindi word for ""test"" — परीका — appearing here as a U-label would (in the Devanagari script). A special form of ""ASCII compatible encoding"" (abbreviated ACE) is applied to this to produce the corresponding A-label: xn--11b5bs1di. A domain name that only includes ASCII letters, digits, and hyphens is termed an ""LDH label"". Although the definitions of A-labels and LDH-labels overlap, a name consisting exclusively of LDH labels, such as"""" is not an IDN."