ISO 3166-1 and country coded Top-Level Domains (ccTLDs)

ICANN, the Internet Corporation for Assigned Names and Numbers is the entity in charge of coordinating the technical management of the Internet domain name system, allocating IP address space, assigning protocol parameters, and managing the root server system.

One of the most important Internet Standards with regard to the Domain Name System is the IETF Standard RFC 1591 Domain Name System Structure and Delegation from 1994. It specifies that "There are a set of what are called top-level domain names (TLDs). These are the generic TLDs (EDU, COM, NET, ORG, GOV, MIL, and INT), and the two letter country codes from ISO 3166."

So the alpha-2 code elements from ISO 3166-1 are used in the Internet as the country code top-level domain identifiers (ccTLDs). There are more than 240 ccTLDs in the Internet. In fact ICANN (or IANA) have created a few ccTLDs (.ac and .uk) which are not based on official list of country codes but on the list of reserved ISO 3166-1 code elements.

ISO is very pleased that such a huge and important application as the Internet domain name system is using ISO's codes for structuring itself. ICANN makes use of our country coding standard very prudently - an attitude which is reflected in their continuing dedication to strictly adhering to our list of code elements without creating new code element assignments of their own.

This last statement serves well as a transition to what needs to be said next about ISO 3166-1 and the Internet domain name system:

For quite some time now, individual persons or organizations interested in obtaining their "own" TLD have been requesting the inclusion of "new" country names into ISO 3166-1 in order to get a new alpha-2 code element from the ISO 3166/MA and subsequently a ccTLD from ICANN. Such requests are absolutely futile, however, because the only way to enter a new country name into ISO 3166-1 is to have it registered in one of the following two sources:

To be listed in the bulletin Country Names you must either be

  • a member country of the United Nations,
  • a member of one of its specialized agencies or
  • a party to the Statute of the International Court of Justice.

The list of names in the code of the UN Statistics Division is based on the bulletin Country Names and other UN sources.

Once a country name or territory name appears in either of these two sources, it will be added to ISO 3166-1 by default.

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