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Pre-ICANN59 Policy Update Webinar

Please RSVP via this form by 13 June 2017. You will receive remote participation details the week of 12 June 2017. The ICANN Policy Development Support Team will host a Policy Update Webinar on Thursday, 15 June 2017 at 10:00 and 19:00...

ICANN Registration System Email Validation

As part of an ongoing process to improve the security of our web applications, the ICANN Registration website will now require that all potential meeting participants verify their email address to complete the registration process. This added...

ICANN Supports the Africa Internet Summit as Part of Its Regional Outreach Efforts

The Internet Corporation for Assigned Names and Numbers (ICANN) is sponsoring and participating in the Africa Internet Summit (AIS), organized by the Internet Numbers Registry for Africa (AFRINIC) and the African Network Operators Group (AfNOG)....

Call for Volunteers as Trusted Community Representatives

The Internet Corporation for Assigned Names and Numbers (ICANN) is seeking interested individuals who wish to act as Trusted Community Representatives (TCRs). These individuals play an important role in managing the Root Zone Key Signing Key...




ICANN History Project | Interview with Peter Dengate-Thrush, ICANN Board Chair (2007-2011)

Peter Dengate-Thrush, ICANN Board Chair (2007-2011), discusses key moments of ICANN’s history and its relationship with the U.S. Government. For more, check out the ICANN History Project page:...


ICANN History Project | Interview with Vint Cerf, ICANN Board Chair (2000-2007)

Vint Cerf, also known as one of the “Fathers of the Internet,” discusses key moments of ICANN’s history and its relationship with the U.S. Government. For more, check out the ICANN History...


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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."