The Domain Name System (DNS) handles Internet domain names (such as www.google.com) and converts them to Internet Protocol (IP) numbers (and the other way around). This makes it easier for Internet users to access locations in the Internet such as websites, by simply looking for the domain name of the website, instead of the IP number associated to it.
From an infrastrastructure point of view, the DNS consists of root servers, top-level domain (TLD) servers, and a large number of DNS servers located around the world.
The DNS includes generic top-level domain (gTLD) and country code top-level domains (ccTLD). There are now over 1200 gTLDs, ranging from traditional ones such as .com, .net, and .org, to new gTLDs (introduced starting 2014) such as .pub,, .ngo, or .游戏 (game). While most gTLDs have an open registration policy, allowing the registration of domain names by any interested individual or entity, there are several gTLDs that are restricted to specific groups. For example, only authorised banking institutions can register domain names under .bank. ccTLDs are two-letter TLDs designating countries or territories (such as .uk for the United Kingdom, .cn for China, and .br for Brazil).
Each gTLD and ccTLD is managed by a registry, whose main responsibility is to maintain and administer a database with all registered domain names. For example, .com is managed by VeriSign, while .uk is managed by Nominet. The actual registration of domain names, by end users (called registrants) is performed though registrars. In the case of gTLDs, the registry and registrar functions are clearly separated. For some ccTLDs, the registry can also act as registrar.
The Internet Corporation for Assigned Names and Numbers (ICANN) ensures the overall coordination of the DNS by developing and implementing policies governing the operation and evolution of the system. For gTLDs, ICANN concludes agreements with registries and accredits registrars. ccTLDs have a special status, in that ICANN does not set rules for how they are administered and managed. There are, however, several ccTLD registries that have concluded some types of agreements with ICANN (such as accountability frameworks, memoranda of understanding, and exchange of letters).
The operational coordination of the DNS is performed through ICANN’s affiliate Public Technical Identifiers (PTI).
The creation of new generic top level domains (gTLDs)
In 2012, after six years of consultations and development of a new policy, ICANN launched the New gTLD Program, opening up the DNS beyond the 22 gTLDs existing at that point. Under the programme, any organisation in the world could apply for a new gTLD, including in non-Latin language scripts, as long as it complied with a series of criteria established in the so-called New gTLD Applicant Guidebook. The introduction of new gTLDs was received with enthusiasm by some stakeholders, who saw this programme as an opportunity to enhance competition and consumer choice in the domain name market. Others expressed concern, especially in relation to the potential need for trademark holders to undertake defensive registrations of domain names in multiple gTLDs, for the purpose of avoiding cybersquatting.
Other concerns were raised by governments represented in ICANN’s Governmental Advisory Committee (GAC), who called for measures aimed to ensure the protection of end-users and preserve competition on the gTLD market. As an example, in the case of gTLDs representing regulated sectors (such as .bank and .pharm), governments have proposed measures aimed to ensure that only entities having the appropriate authorisations to operate in such sectors could register domain names in such gTLDs.
Although the debate on the introduction of new gTLDs continues, the programme is up and running. There are also discussions within the ICANN community over the opportunity of launching subsequent rounds of applications for new gTLDs.
For more details on the current status of the New gTLD Program, consult the dedicated process page.
The management of country code top level domains (ccTLDs)
The management of ccTLDs involves three important issues. The first concerns the often politically controversial decision regarding the registration of codes for countries and entities with unclear or contested international status. From the beginning, IANA used the principle of allocating domain names in accordance with the ISO 3166 standard for country codes.
The second issue concerns who should manage ccTLDs. Currently, there are several ccTLD registry models in place, with the registry functions being performed by public entities, private companies, or multistakeholder structures. In some countries, the management of ccTLDs is subject to government regulations. Some governments who initially had no involvement in ccTLD management have been trying to gain control over their country domains, seen as national resources. For example, South Africa used its sovereign rights as an argument in win control of its ccTLD. Transition (re-delegation) of a ccTLD to a new registry is approved by ICANN only if there is no opposition from any of the interested stakeholders within the concerned country.
The third issue relates to the fact that, unlike the case of gTLDs, ICANN imposes no rules as to who and how should manage a ccTLD. ICANN goes only as far as delegating or re-delegating ccTLDs on the basis of some high-level guidelines aimed at ensuring that the ccTLD registry is technically competent to manage it, and has support from the local community. In 2005, ICANN’s GAC adopted a set of Principles and Guidelines for the delegation and administration of country code top level domains, intended to serve as a guide to the relationship between governments, ccTLDs, and ICANN. Although some ccTLD registries (e.g. Brazil, Chile, Netherlands) have concluded some type of agreements with ICANN, and many registries are represented in ICANN’s Country Code Names Supporting Organization (ccNSO), there are several ccTLDs that have shown reluctance to become part of the ICANN system.
The creation of internationalised domain names (IDNs)
The Internet was originally a predominantly English-language medium. Through rapid growth, it has become a global communication facility with an increasing number of non-English-speaking users. For a long time, the lack of multilingual features in the Internet infrastructure was one of the main limits of its future development.
In May 2010, after a long testing period and political uncertainties, ICANN started approving TLDs in a wide variety of scripts, including Chinese, Arabic, and Cyrillic. IDNs have been introduced in several countries and territories as equivalent to their Latin country code top level domains (ccTLDs). For example, in China, 中国 has been introduced in addition to .cn, while in Russia, рф has been introduced in addition to .ru. IDNs are also part of ICANN’s new gTLD programme, allowing for the registration of new top level domains (gTLDs) in scripts other than the Latin one; for example, .сайт (website) and .онлайн (online) are among the new TLDs available to the public.
The introduction of IDNs is considered to be one of the main successes of the Internet governance regime. However, limitations remain, as universal acceptance is still a challenge when it comes to issues such as functional IDN e-mail addresses and recognition of IDNs by search engines.
Transition of the US government role
Since its creation, in 1998, and until 1 October 2016, ICANN managed the DNS on the basis of a contract with the US government, through the National Telecommunications and Information Administration (NTIA). In line with this contract, the US government acted as steward of the DNS, as every major change made within the system (such as the approval of a new gTLD) required its formal validation. In March 2014, NTIA announced its intention to transition this stewardship role to the global multistakeholder community. As requested by NTIA, ICANN launched a process for the development of a transition proposal. At the same time, work began on the elaboration of a set of recommendations for enhancing ICANN’s accountability towards the Internet community (seen as a necessary step in the context of the transition). The work carried out by the ICANN community resulted in a transition and an accountability proposals, which were accepted by the US government in June 2016, as being compliant with its requirements.
On 1 October 2016, the IANA functions contract between the US government and ICANN expired, and the stewardship of the IANA functions was transitioned to the global multistakeholder community. In practical terms, the transition meant two major changes within ICANN: (1) the establishment of PTI as the IANA functions operator, and, therefore, a more clear separation between ICANN’s technical and policy-making functions; (2) the creation of an ‘empowered community’ – made up of most of ICANN’s advisory committees and supporting organisations – able to enforce a set of community powers such as removing members of the ICANN Board and rejecting ICANN budgets or changes to the ICANN bylaws. See IANA transition and ICANN accountability for more details.