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Announcements

Guidelines for Developing Reference Label Generation Rulesets (LGRs) for the Second Level

Forum Announcement: Comment Period Opens on Date: 5 November 2015 Categories/Tags: Second-Level Domains Purpose (Brief): To facilitate and improve consistency of testing and stability...

Apply Now: Experts in Consumer Protections, Economics and Security Needed for New gTLD Program Review

ICANN today announced that it extended the application deadline for participation on the community-based team that will review the New gTLD Program in regard to competition, consumer trust and consumer choice (CCT). Experts in consumer...

ICANN and OAS to Work Together to Increase Regional Cyber-Security

The Internet Corporation for Assigned Names and Numbers (ICANN) and the General Secretariat of the Organization of American States (OAS) through their Executive Secretariat of the Inter-American Committee Against Terrorism of the Secretariat for...

ICANN Audited Financial Statements for FY15 Have Been Published

ICANN continues to provide accountability and transparency regarding its financial results, with another unqualified audit report from the independent auditors, BDO LLP. The Report of Independent Auditors and Financial Statements for ICANN for the...

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The ICANN Journey

Everyone is welcome at ICANN! You don’t need to be an expert to participate (hint: most aren’t when they start out). See one person’s journey from beginner to Working Group Chair for a look inside...

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Valerie Tan previews her first term on the GNSO Council

Valerie Tan, NomCom Appointee to the GNSO Council (2015-2017), reflects on diversity in the GNSO and the importance of the rapidly growing Asian market for the DNS industry.

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Transition Program Facilitation Meeting - 9 July 2015

Coordination call for the IANA Stewardship Transition and Enhancing ICANN Accountability Processes.

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CCWG-Accountability Co-Chair Mathieu Weill at ICANN53

Mathieu Weill, Co-Chair of the CCWG-Accountability reports on the chairs' briefings to various stakeholder groups today at ICANN53 in Buenos Aires.

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Blog Posts

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ICANN at the Internet Governance Forum (IGF) 2015

Volume 11: An Update on IANA Stewardship Discussions

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What is a Man in the Middle Attack?

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