generic top level domains (gTLDs)

This page looks at the global or generic top level domain (gTLD) spaces: those that are not based on a national code and those (such as dot-mil and dot-edu) have gTLD status because of an accident of history.

It covers -

• the com, net and org gTLDs
• dot-int - international organisations such as WIPO and the ITU
• dot-eu - the European Union gTLD
• US government domains such as dot-mil
• the edu gTLD
• additional gTLDs such as aero, museum, travel and biz

     com, net, org

Dot-com, dot-net and dot-org are the three domain spaces with which most people are familiar. They are not restricted to US citizens or entities (for example the registrant of a dot-com does not need to be based or legally registered in the US).

The cost of registration is significantly lower than that in many national domains (noted on the following page of this profile) and is one reason why the dot-com has become the global 'default' domain.

In discussing the size of the web we have noted suggestions that as of October 2002 there were over 21.2 million dot-com registrations, 3.6 million dot-nets and around 2.3 million dot-orgs. Those figures have increased over successive years, although the number of discrete sites has not grown to the same extent because much registration has been opportunistic or as part of monetisation. Some comparisons are provided in the note here.

     int

The dot-int TLD is used only for registering organizations established by international treaties between governments. As of February 2003 it appears to comprise around 94 domains.

     eu

The European Union has established a dot-eu gTLD to cover EU entities, with establishment of a registry (EURid) and addition of the TLD to the internet root in May 2005.

Dot-eu is meant to cover businesses having their registered office, central administration or principal place of business within the European Community; organisations established within the EC and individuals resident within the EC.

     US government domains

In the October 1984 Domain Requirements RFC (RFC 920) Postel & Reynolds proposed a set of initial gTLDs including dot-com (commercial), dot-edu (education), dot-gov (government), dot-mil (military) and dot-org (organisation). An additional gTLD - dot-net - was added prior to implementation of those domains in January 1985 and has gained more attention than the two US government TLDs.

The dot-gov TLD was initially reserved exclusively for the United States Government: Federal and State agencies and Federally-recognized Indian tribes (the latter in a .nsn.gov 2LD). As of February 2003 it appeared to comprise around 1,350 domains.

The coverage of dot-gov has subsequently expanded to encompass -

• US federal government entities (some of which also appear in the .fed.us 2LD)
• agencies listed in the US Government Manual  
• Cross-Agency Collaborative organizations 
• Federally recognized Indian Tribes (in the NSN 2LD) 
• US State government entities 
• US City and Township government entities 
• US county and parish government entities 

As of early 2007 there were some 3,903 active websites, of which 1,986 were attributed to state, local and county entities (out of some 3,000 counties and 19,000 municipal governments).

Dot-gov is operated by the US General Services Administration (GSA).

The dot-mil TLD is exclusively reserved for the United States armed forces and as of February 2003 appeared to comprise around 80 domains. It is operated by the US DoD Network Information Center. There are equivalent 2LDs in some national domain spaces.

     edu

The dot-edu domain is reserved for educational institutions in the United States and was restricted to bodies that grant four-year degrees. Liberalisation as part of delegation of administration from VeriSign to Educause, a nonprofit body, in 2001 extended availablity of the domain to a wide range of institutions, including acupuncture schools and Bible colleges (with around 7,500 new dot-edu names assigned to 6,000 institutions in February 2003). As of January 2007 there were around 7,400 'live' .edu names.

The dot-edu gTLD initially comprised most of the net and as late as 1996 the dot-com and dot-net gTLDs contained only 1.8 times as many hosts. By 2000 the dot-com and dot-net domains were six times larger than dot-edu; that disparity will continue to increase.

     additional gTLDs

ICANN is moving (its critics say moving too slowly) to establish new generic TLDs. Some proponents have argued for sectoral gTLDs. Others propose regional gTLDs, for example on the basis that some cities have a distinct identity and have both a population and economomy that is larger than many countries. Particular proposals are discussed in the following page of this profile.

As of 2006 ICANN has authorised establishment of a handful of sectoral GTLDs.

Those addition TLDs are sometimes described as "experiments to test demand feasibility" for the creation of a range of other domains. As discussed later in this profile, some clash with existing or new alternative domains established by enthusiasts/entrepreneurs and unrecognised by ICANN (and thus not readily accessible from most devices on the net).

The additional TLDs include -

.museum, for organisations authorised by the International Council of Museums (ICOM). As of April 2003 around 669 names had been registered, predominantly from the US and often with multiple names for the one entity

.biz, a domain that parallels dot-com and is expected to be colonized by many of the entities that have dot-com registrations. It is being marketed by NeuLevel. As of September 2002 there were around 770,000 dot-biz registrations (up from 700,000 in April), with utilisation (ie activation of live web sites) variously estimated at between 1% to 25%. Growth has slowed from approximately 1,500 to 1,000 names per day.

.info, an 'unrestricted' space that was marketed as a gTLD for directory services and handled by Afilias. As of October 2002 there were around 920,000 dot-info names. As with dot-biz there are a significantly smaller number of live sites (many registrations appear to be wholly 'defensive') and growth has slowed to under 1,000 new registrations per day

.name, a domain for personal names, being marketed by Global Name Registry (GNR). It appears that around 85,000 dot-name registrations had occurred from January to end September 2002, with an estimated 71% involving GNR's complementary email service. As of October 2002 the growth in dot-name registrations was around 750 names per day. At the end of 2003 GNR was moving to allow registrations at the 2LD level

.pro, aimed at accountants, lawyers, physicians and other professionals. Inclusion in the gTLD would be restricted to certified entities (tacitly operating a gTLD as a meta-trustmark, with RegistryPro's chief operating officer Sloan Gaon commenting "We're looking to provide a gated community for professionals"). As of May 2003 the space was to be structured as .law.pro (legal and related services), .cpa.pro (accountancy and related services, US only) and .med.pro (medical and health-related services) but in October 2003, in an apparent admission of underwhelming demand, the registry moved towards registration at the 2LD level (eg name.pro rather than name.cpa.pro). The registry is to be operated on a for-profit basis by a subsidiary of dot-com registrar Registry.com

.aero, relating to the air transport sector. The registry (with five commercial registrars) is to be operated on a not-for-profit basis by SITA. The 2002 ATA/IATA Joint Passenger Services conference endorsed use of two-character airline designator codes, followed by .aero, to assist travellers to gain quick access to airline sites and the Airports Council International (ACI) has endorsed a "fully predictive naming convention for the use of three and four letter location codes".

.coop, concerned with cooperatives. It has been established under the auspices of the Indian National Dairy Development Board, the Cooperative League of Puerto Rico, US National Cooperative Bank, UK Co-operative Union, US National Rural Telecommunications Cooperative, International Co-operative Alliance (ICA), US National Cooperative Business Association (NCBA) and UK service provider Poptel.

.travel, which according to the registry is "designed to serve the global travel and tourism community by developing products and services that promote the efficiencies and convenience of e-commerce for all bona fide travel companies and tourism organizations on the Internet ... improved Internet identity, creation of advanced distribution channels, and the establishment of an ever-stronger level of trust between the industry and its customers". It will encompass "airlines, theme parks, restaurants, tourism offices and others in travel and tourism" and "may grow to include retailers of luggage".

.mobi, concerned with web delivery of information to mobile phones and similar devices.

Perspectives on the uptake of some of those gTLDs are provided in writings by Ben Edelman and others. They include

Survey of Usage of the .BIZ TLD, a June 2002 paper by Edelman & Jonathan Zittrain

.NAME Registrations Not Conforming to .NAME Registration Restrictions, a May 2002 paper by Edelman

A Case Study of Disputed Registrations in .BIZ, A Case Study of Domain Registrations by Swarthmore Associates and John Kirkland, a May 2002 paper by Edelman

The Viability of Market-Based Regulation of Internet Top-Level Domains, a 2002 thesis (PDF) Alex Houston

The success of the new TLDs is uncertain: establishment will require significant promotional resources. As of August 2002 the uptake of the new commercial TLDs (other than for defensive purposes) and dot-museum appeared to be underwhelming.

ICANN's procedures for creating new gTLDs and reassigning existing gTLDs were criticised in a 2004 OECD report on Generic Top Level Domains: Market Development & Allocation Issues (PDF).

    next page  (new gTLDs)