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Address Supporting Organization (ASO) Review

The Board took action on 12 June 2022 to defer the Third Review of the Address Supporting Organization. See the Board resolution here.

The Address Supporting Organization (ASO) is one of the supporting organizations that the ICANN Bylaws prescribe as "formed through community consensus". The purpose of the ASO is to advise the Board with respect to policy issues relating to the operation, assignment, and management of Internet addresses. The ASO is the entity established between ICANN and the Number Resource Organization (NRO), an organization of the existing regional Internet registries (RIRs).  For more information on the ASO, click here.

ASO Organizational Review

The goal of the review, to be undertaken pursuant to such criteria and standards as the Board shall direct, shall be to determine (i) whether that organization, council or committee has a continuing purpose in the ICANN structure, (ii) if so, whether any change in structure or operations is desirable to improve its effectiveness and (iii) whether that organization, council or committee is accountable to its constituencies, stakeholder groups, organizations and other stakeholders.

These periodic reviews shall be conducted no less frequently than every five years, based on feasibility as determined by the Board. Each five-year cycle will be computed from the moment of the reception by the Board of the final report of the relevant review Working Group.

The graphic below illustrates phases and status of each review - a  indicates that all activities within a given phase have been completed.  The chart that follows the graphic provides further details of key activities and milestones within each phase – you can view these details by clicking on each of the phases in the graphic.  The table also contains links to relevant documents.


PhaseActivityDescriptionStart DateDocuments
Plan ReviewRFP for Consulting ServicesAnnouncement for Request for Proposals for Consulting Services: Independent Review of the ICANN Address Supporting Organization18 Nov 2016
Selection of Independent ExaminerAnnouncement of Selection of Independent Examiner, ITEMS International2 Feb 2017
Conduct ReviewFinal Report of ITEMS InternationalReview of the ICANN Address Supporting Organization (ASO) Final Report3 Aug 2017
Public Comment on ASO Review: Final ReportPublic Comment on Address Supporting Organization (ASO) Review Final Report8 Aug 2017
Response to Review RecommendationsNRO EC and ASO AC joint response to the 2017 independent ASO review recommendations8 Jan 2018
Implement ImprovementsStatus of implementationRecommendation Implementation Status31 Aug 2017
Standard Operating ProceduresDeferral of Third ASO ReviewDeferral of the Third ASO Review (ASO3)12 Jun 2022


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."