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HEADQUARTERS

  • Los Angeles, California, USA

    12025 Waterfront Drive, Suite 300
    Los Angeles, CA 90094-2536, USA

    Phone: +1 310 301 5800
        Fax: +1 310 823 8649

REGIONAL OFFICES

  • Istanbul, Turkey

    Hakki Yeten Cad. Selenium
    Plaza No:10/C K:10
    34349 Istanbul, Turkey

    Tel: +90 212 999 6222

  • Singapore

    South Beach Tower
    38 Beach Road, Unit 04-11
    Singapore 189767

    Phone: +65 6816 1288

  • Montevideo, Uruguay

    La Casa de Internet de Latinoamérica y el Caribe
    Rambla República de México 6125
    11400 Montevideo, Uruguay

    Phone: +598 2604 2222 ext 5701
        Fax: +598 2604 2222 ext 4112

  • Brussels, Belgium

    6 Rond-Point Schuman
    B-1040 Brussels, Belgium

    Phone: +32 2 894 7414

ENGAGEMENT CENTERS

  • Beijing, China

    5th Floor, No. 1 Building, Software Park
    Chinese Academy of Sciences
    4 South 4th Street
    Zhongguancun, Haidian District, Beijing, China

    queries.beijingec@icann.org

  • Geneva, Switzerland

    Regus Center
    Rue du Rhône 14
    1204 Geneva, Switzerland

    Phone: +41 22 819 1844
        Fax: +41 22 819 1900

  • Nairobi, Kenya

    Regus Center
    17th Floor
    JKUAT Towers, Kenyatta Avenue
    PO BOX 15168-00400
    Nairobi, Kenya

    Phone: +254 (0)20 5157029
        Fax: +254 (0)20 5157001

  • Washington, D.C., USA

    801 17th Street NW, Suite 400
    Washington, DC 20006, USA

    Phone: +1 202 570 7240
        Fax: +1 202 789 0104

If you require assistance or have a question, please visit Global Support

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""icann.org"" is not an IDN."