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Profile image for Fabien Betremieux

Fabien Betremieux

France

GAC Relations Advisor

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John Bond

Principal DNS Engineer

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John Crain

Chief Security, Stability & Resiliency Office

Developing WorldTechnology

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Kim Davies

Director, Technical Services

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Gustavo Lozano Ibarra

Technical Services Director

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Darren Kara

United States

DNS Engineering Strategy Manager

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Alexandra Kulikova

Russian Federation

Head of Global Stakeholder Engagement, Eastern Europe and Central Asia

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Edward Lewis

United States

Sr. Technologist

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David Olive

United States

SVP, Policy Development Support

Civil SocietyDNS MarketplaceGovernmentTechnology

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David Piscitello

VP of Security and ICT Coordinator

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David Soltero

Lead DNS Engineer

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."