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ICANN's Technical Functions

As a technical coordinating body, ICANN performs a variety of functions related to the Internet's unique identifiers. These include operational functions, collaboration, coordination and engagement.

ICANN technical engagement occurs in the following key areas of the organization:

  1. IANA functions (includes (Root key signing infrastructure for DNSSEC (
  2. Office of the CTO (OCTO)
    • Technology and Research
    • Identifier System Security, Stability & Resiliency (DNS resiliency architecture, Capacity building and Awareness on Security issues related to DNS)
    • Internet Technology and Health Indicators
  3. Information System and Innovation (includes L-root)
  4. Global Domains Division technical team


  1. IANA function

    Part of ICANN Operational functions include the maintenance or key Global Registries (Protocol Parameters, Top level IP number Prefixes and Top level Domain name delegation) under the Internet Assigned Numbers Authority (IANA) functions, and the Time Zone Database (, which contains the code and data that represents local time around the globe.

    The IANA Functions are regarded as: (organize this in table with link to associated policy)

    1. Coordination of the assignment of technical protocol parameters (
    2. The management of the .arpa TLD (
    3. Performance of administrative functions associated with root zone management (
    4. Managing and assessing requests for root zone file changes.(
    5. Managing change requests for gTLD registry information in the WHOIS database (registration data) (see also
    6. Implementing Registry information changes related to the country code TLDs assignment in accordance with established policy
    7. Implementing decisions related to the delegation and redelegation of generic TLDs in accordance with ICANN policy (this should be according to GNSO policies)
    8. Undertaking projects to increase root zone automation
    9. Managing root DNSSEC keys and supporting infrastructure
    10. Providing a resolution process for handing customer service queries associated with the IANA functions
    11. Allocating and maintaining global Top level Internet number resources prefix Registry (
    12. Performing other services (operating .int TLD,, implementing modifications in the performance of the IANA functions)
  2. Office of the CTO (OCTO)

    The Office of the Chief Technology Officer includes Internet Technology Research and Analytics, contributions to the IETF, and coordination of the Technical Experts Group. Their mission includes:

    • Researching issues related to the Internet's system of unique identifiers (domain names, IP addresses/AS numbers, protocol parameters)
    • Supports improving the Security, Stability, and Resiliency of those identifiers
    • Providing internal and external "Internet Technology Resources"
    • Training, data, research, information, consulting, etc.
    • Conducting technical engagement and outreach in partnership with the Global Stakeholder Engagement group

    Major initiatives for the OCTO team have included: Implementation of Stewardship of the IANA Functions --; DNSSEC Key Signing Key Rollover Plan --; Identifier Technologies Health Indicators (ITHO);

    The Identifier Security Stability and Resiliency team is one arm of the OCTO group. ICANN Security, DNS and DNSSEC capacity building training, and participating in technical community groups; ICANN incident response (ICANN is a member of the Forum for Incident Response and Security Teams,; work with trusted security community activities such as the AntiPhishing Working Group, the Messaging AntiAbuse Working Group, regional TLD organizations, registry operators, and public safety groups.

  3. Information System and Innovation

    Other operational functions include the work of the Office of the Chief Information and Innovation Officer, whose team is responsible for monitoring and maintenance of ICANN systems and technical operations, corporate security, and Information Technology and the ICANN DNS Engineering Team (, which administers L-root and ICANN's DNS network services.

  4. GDD Technical support

    The Global Domains Division has a technical services team supporting gTLD Registries and Registrars under contract with ICANN. This includes contracting for Emergency Backend Registry Operators (, Registry and Registrar Data Escrow, operating the Centralized Zone Data Service ( and Registry Services Evaluation Process ( The GDD team also supports Internationalized Domain Names (IDNs) through the management of the IDN ccTLD Fast Track Process, the IDN Guidelines, the IDN Variant Program, Root Zone Label Generation Ruleset, and coordination of Label Generation Panels (see


All these areas engage and collaborate with other elements of the Internet Technical ecosystem such as: ISOC, the RIRs (NRO), W3C et others.

Engagement functions include interaction with community-facing supporting organizations and advisory communities such as SSAC and RSSAC, and the Address Supporting Organization, coordination of technical sessions at ICANN meetings (Tech Day, DNSSEC Workshop, working sessions of SSAC, RSSAC, ASO) or at community meetings (such as RIRs, IETF, national, regional and global IGF events), participation in technical conferences, talks or other engagements on behalf of ICANN.

For more information on SSAC, see

For more information on RSSAC, see

For more information on the Address Supporting Organization, see

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."