Second-level domain

In the Domain Name System (DNS) hierarchy, a second-level domain (SLD) is a domain that is directly below a top-level domain (TLD). For example, in example.com, example is the second-level domain of the .com TLD.

Second-level domains commonly refer to the organization that registered the domain name with a domain name registrar. Some domain name registries introduce a second-level hierarchy to a TLD that indicates the type of entity intended to register an SLD under it. For example, in the .uk namespace a college or other academic institution would register under the .ac.uk ccSLD, while companies would register under .co.uk.

In Australia, currently there are 16 active second-level domains, all managed by auDA.

Open second-level domains (available for the public):

Closed second-level domains (restricted to certain sectors):

Community Geographic Domain Names (restricted to certain geographic regions for community use):

Historically, Australia's country code top-level domain was .oz. After the introduction of the .au ccTLD, the domains in .oz were moved under the oz.au second-level domain.

In Austria there are two second-level domains available for the public:

The second-level domain

In France, there are various second-level domains available for certain sectors, including

There are 21 active second-level domains in Hungary, including:

The registration of second-level domains is managed by the Council of Hungarian internet providers.

Open second-level domains (available for the public):

Closed second-level domains (restricted to certain sectors):

There are eight Second Level Domains:

Registration of other second-level domain names directly under .il is not supported.

Hebrew third level domains such as האינטרנט.org.il are available since 2010.

Second-level domain registrations are handled jointly by the official registry service CCTLDRU and private companies. There are currently 133 active second-level domains available for registration. This large number is because every geographical region has its own second-level domain, such .volgograd.ru for the Volgograd Region, .irkutsk.ru for the Irkutsk region or msk.ru for Moscow. There also second–level domains for specific sectors, such as ac.ru for academic institutions, com.ru for commercial enterprises or int.ru for international organizations.

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