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Request for Proposal: gTLD Marketplace Health Index Assessment

The Internet Corporation for Assigned Names and Numbers ("ICANN") is seeking to identify one or more suppliers qualified to (a) assess a proposed framework for domain name system (DNS) marketplace indicators, (b) create a detailed taxonomy of the...

ICANN Board to Hold Public Session and Board Meeting During Montevideo Workshop

LOS ANGELES – 13 September 2017 – The ICANN Board will be holding one public session and a Board Meeting during its upcoming workshop in Montevideo, Uruguay, which will be taking place from 20-23 September, 2017. The agenda of the sessions is...

ICANN Publishes NomCom2 Review Survey for Community Input

LOS ANGELES – 12 September 2017 – Today, the Analysis Group, the independent examiner conducting the second review of the ICANN Nominating Committee (NomCom2), announced a survey to collect input from those who have interacted with NomCom...

WEBINAR: Compliance & Consumer Safeguard Overview

LOS ANGELES – 11 September 2017 – The Internet Corporation for Assigned Names and Numbers (ICANN) today announced that ICANN will host an interactive webinar on 25 September 2017 to discuss Compliance and Consumer Safeguard matters within ICANN’s...




Preview | Interview with John Crain, Chief SSR Officer at ICANN

Steve Crocker and John Crain, Chief Security, Stability & Resiliency Officer at ICANN, discuss ICANN's early days.


ICANN Accountability Indicators

In the spirit of accountability and transparency, the indicators show the latest progress towards achieving ICANN’s strategy. Visit: to learn more.

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Update on New gTLD Subsequent Procedures

ICANN Policy Analyst Ariel Liang speaks with Co-Chair Jeff Neuman of the Generic Names Supporting Organization (GNSO) Policy Development Process Working Group on the New Generic Top-Level Domain...

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Recapping GNSO Activities at ICANN59 and Looking Ahead to ICANN60

The leadership of the Generic Names Supporting Organization (GNSO) Council speaks to ICANN Policy Analyst Ariel Liang, detailing the issues that have framed ICANN59 discussions, as well as the...


Blog Posts

LACNIC: Celebrating 15 Years of Regional Excellence

Chairman’s Blog: Previewing the Montevideo Workshop


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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."