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Community-developed Framework for Registry Operator's Response to Security Threats Now Available

LOS ANGELES – 20 October 2017 – The Internet Corporation for Assigned Names and Numbers today announced a voluntary Framework for Registry Operator's Response to Security Threats (Framework). The Framework provides guidance to registry operators...

ICANN Board to Hold Public Sessions and Board Meeting During Abu Dhabi Workshop

LOS ANGELES – 20 October 2017 – The ICANN Board will be holding two public sessions and a Board Meeting during its upcoming workshop in Abu Dhabi, which will be taking place from 27-29 October, 2017. The agenda of the sessions is provided...

ICANN History Project Explores the Early Days of ICANN

LOS ANGELES – 19 October 2017 – ICANN is pleased to announce the unveiling of the second track of the ICANN History – The Early Days of ICANN. The ICANN History Project captures stories from those who shaped ICANN's past and its evolution over...

Internationalized Domain Name (IDN) Implementation Guidelines – Second Public Comment

Open Date: 19 October 2017 Close Date: 10 December 2017 Originating Organization: Global Domains Division Categories/Tags: Second-Level Domains Brief Overview: The Internationalized Domain Name...




ICANN History Project | Interview with Ira Magaziner [102E]

Ira Magaziner, Senior Policy Advisor and Chief Internet Policy Advisor to President Clinton (1993-1998), discusses key moments of ICANN’s history and its relationship with the U.S. Government....


ICANN 历史项目 | 伊拉•马加齐纳访谈,克林顿总统高级政策顾问(1993-1998 年)[102Z]

伊拉•马加齐纳,克林顿总统高级政策顾问兼首席互联网政策顾问(1993-1998 年),谈论了 ICANN 发展历史的重要时刻,以及该组织与美国政府之间的关系。 如需了解更多信息,请查看 ICANN 历史项目页面:

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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."