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Thick WHOIS Registration Data Directory Services Requirements to Take Effect

LOS ANGELES – 1 February 2017 – The Internet Corporation for Assigned Names and Numbers (ICANN) today announced that all ICANN gTLD contracted parties must update their registration data directory services to comply with the Thick Whois Transition Policy for .COM, .NET and .JOBS and Registry Registration Data Directory Services Consistent Labeling and Display Policy.

The policies require all gTLD registrations to be Thick with a consistent labeling and display of WHOIS output. gTLD registry operators currently providing Thin WHOIS services – .COM, .NET and .JOBS – must submit all new domain name registrations as Thick WHOIS by 1 May 2018. These registries must also migrate all data required for Thick WHOIS services for existing domain names by 1 February 2019. These changes are required by the Thick Whois Transition Policy for .COM, .NET and .JOBS. In addition, registries and registrars are required to implement the data specifications defined in the Registry Registration Data Directory Services Consistent Labeling and Display Policy by 1 August 2017. ICANN has notified contracted parties of their new responsibilities.


ICANN's agreements with accredited registrars and with gTLD registry operators require compliance with various specifically stated procedures and "consensus policies." Consensus policies are developed through a bottom-up, multistakeholder policy development process in accordance with ICANN Bylaws. The ICANN Board adopted GNSO consensus policy recommendations regarding the use of Thick WHOIS by all gTLD registries on 7 February 2014. The recommendations state that, "The provision of Thick Whois services, with a consistent labeling and display as per the model outlined in specification 3 of the 2013 [Registrar Accreditation Agreement], should become a requirement for all gTLD registries, both existing and future."

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ICANN's mission is to help ensure a stable, secure and unified global Internet. To reach another person on the Internet, you have to type an address into your computer - a name or a number. That address has to be unique so computers know where to find each other. ICANN helps coordinate and support these unique identifiers across the world. ICANN was formed in 1998 as a not-for-profit public-benefit corporation and a community with participants from all over the world. ICANN and its community help keep the Internet secure, stable and interoperable. It also promotes competition and develops policy for the top-level of the Internet's naming system and facilitates the use of other unique Internet identifiers. For more information please visit:

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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."