Top-Level Domain
The domain name system allows users to refer to websites and other Internet resources using names rather than the all-numeric IP addresses assigned to each computer on the Internet. Each domain name consists of a series of character strings separated by dots. The right-most string is its top-level domain (TLD), and every TLD is managed by a single [[registry]
Overview from 1983 to 2021[edit | edit source]
| Dates | TLDs | use | reason | significance |
|---|---|---|---|---|
| 1983 | .no | ccTLD | Norway | the first ccTLD |
| October 1984 | introduced: .com, .net, .org | open | any person or entity is permitted to register | the original TLDs |
| October 1984 | introduced: .edu, .gov, .mil | limited (sponsored) | for higher educational institutions, United States governmental entities and agencies, and divisions, services and agencies of the United States Department of Defense, respectively | the original TLDs |
| 1985 | .us, .uk .il | ccTLDs | USA, UK, Israel | second, third, and fourth ccTLDs |
| 1986 | .au, .de, .fi, .fr, .is, .kr, .nl, .se | ccTLDs | Australia, Denmark, Finland, France, Iceland, South Korea, Netherlands, Sweden | the next 8 ccTLDs |
| November 3, 1988 | introduced: .int | limited (sponsored) | for organizations, offices, and programs endorsed by a treaty between two or more nations | in response to NATO request |
| 1998 | Domain deregulation; ICANN is formed to oversee Internet names and numbers | |||
| May 2000 | .arpa | limited (sponsored) | all Internet infrastructure databases | |
| November 16, 2000 | approved: .aero, .biz, .coop, .info, .museum, .name, .pro | sponsored gTLDs | ||
| Approved: .asia, .cat, .jobs, .mobi, .tel, .travel | sponsored gTLDs | |||
| April 2011 | introduced: .xxx | sponsored gTLD | ICM Registry had been submitting this sTLD for pornographic sites since 2000 | |
| 2012 | introducted: .post | sponsored gTLD | ||
| Community TLDs | for a defined community consisting of a restricted population | |||
| June 20, 2011 | ICANN Board votes to dramatically increase the number of gTLDs from the 22 already in operation | |||
| June 13, 2012 | Reveal Day: 1,930 applications for new gTLDs submitted; 751 of which were contest | |||
| July 15, 2013 | сайт, онлайн, شبكة , 游戏 | First four new gTLD aggreements signed | ||
| November 9, 2014 | 400th gTLD was delegated | |||
| 20 May 2017 | ccTLDs | 255 ccTLDs delegated | ||
| June 2020 | IDN ccTLDs | 61 IDN ccTLDs approved | ||
| March 2021 | IANA lists 1589 TLDs (1503 in use, 67 not assigned/revoked, 8 retired, 11 test domains) |
Varieties of TLDs[edit | edit source]
There are different types of TLDs.
gTLDs[edit | edit source]
- brand TLDs - corporations use their corporate name as their website's top-level identifier instead of .com or .biz domain space
- community TLDs relate to local events, gatherings, or organizations.
- geoTLDs represent geographical or regional areas that are not countries with three or more ASCII characters.
- hSTLDs
- nTLDs - domains that were introduced beginning in October 2013
- sTLDs - has a sponsor for a specific purpose, such as to represent a specific ethnic community, professional group, or geographical location.
ccTLDs[edit | edit source]
Country-code TLDs are delegated to a designated ccTLD registry, which is operated by a ccTLD Manager, according to local policies that are adapted to meet the economic, cultural, linguistic, and legal circumstances of the country or territory involved.
- TLDs with two ASCII characters have been established for over 250 countries and external territories.
- TLDs with non-ASCII characters designated for a country or geographic region.
Operating Mode[edit | edit source]
TLDs operate in different manners but can be categorized in some simple ways:
- Open - Operating and offering both registration and resolution services.
- Closed - Not accepting registrations, may be resolving evergreen/legacy/infrastructure subdomains.
Level of Restriction[edit | edit source]
- Unrestricted - If there are no requirements that must be met in order to register a name under a TLD, that TLD is Unrestricted.
- Restricted - Requiring Local Physical Address, Local Tax ID, or other specific criteria to qualify.
Reserved Names[edit | edit source]
- country code top-level domains
- related to ICANN
- related to IANA functions
- names of countries and territories
- names of international and intergovernmental organizations
- names that a registry operator uses to operate the gTLD