ICANN Acronyms and Terms

ICANN has hundreds of acronyms and terms, which can be confusing. We created this multilingual tool to help explain what these terms mean and facilitate your work within the ICANN community.

ICANN Acronyms and Terms

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21-25 of 25 results

stub resolver

A simple resolver that is a part of the operating system on an Internet user’s computer. When a user clicks a link or types a uniform resource locator (URL) in a web browser, the stub resolver sends a recursive query to a designated resolver. A recursive query instructs the resolver to either return the Internet Protocol (IP) address for the requested resource or return an error. Stub resolvers do not accept referrals to other name servers.


A domain that resides within a higher-level domain in the Domain Name System hierarchy. For example, the domains community.icann.org and gnso.icann.org are subdomains of the second-level domain icann.org. The domain icann.org is a subdomain of the top-level domain .org.

Subdomains can be delegated to specific entities. Registrars, for example, delegate second-level domains to registrants. The registrants can then delegate subdomains within their second-level domains.

Sunrise Period

In the New Generic Top-Level Domain Program (New gTLD Program), a period of at least 30 days during the launch of a new gTLD. During this period, trademark holders have an opportunity to register domain names corresponding to their marks before domain name registration is generally available to the public.

Sunrise Service

A service provided by the Trademark Clearinghouse (TMCH) that allows trademark holders to register domain names associated with their marks before registration is generally available to the public. To use this service, trademark holders must have their marks and proof of use verified by the TMCH.

Registries for new generic top-level domains are required to offer the Sunrise Service for at least 30 days.

Supporting Organization(SO)

A formally recognized body under the ICANN Bylaws that is charged with developing policy recommendations for a particular area of ICANN's operations. Supporting Organizations are composed of volunteers from the community. The Bylaws recognize three SOs:

Besides developing policy recommendations, SOs select directors for designated seats on the ICANN Board and participate in the nominating process to fill open Board positions.