Changes

Acronym: '''T'''op '''L'''evel '''D'''omain   

The '''T'''op '''L'''evel '''D'''omain  ('''TLD''') is always the last part of a domain name, such as [[.com]], [[.net]], [[.us]], etc.<ref>[http://www.pcmag.com/encyclopedia_term/0,2542,t=TLD&i=52942,00.asp TLD]</ref> Each TLD is managed by a single [[:Category:Registries|Registry]].

 

The '''TLD''' is always the last part of a domain name, such as [[.com]], [[.net]], [[.us]], etc.<ref>[http://www.pcmag.com/encyclopedia_term/0,2542,t=TLD&i=52942,00.asp TLD]</ref> Each TLD is managed by a single [[:Category:Registries|Registry]].

==History==

==History==

The need for a hierarchical [[DNS]] arose with the popularity of the Internet in academic spheres in the early 1980s; which eventually necessitated a de-centralized Internet. Communications between [[The Stanford Research Institute NIC]] and other institutions include plans to create a hierarchical [[DNS]], found in  [http://www.rfc-editor.org/rfc/rfc805.txt RFC 805], a group document from 1982. This document  outlines many of the basics of the eventual [[DNS]], including the need for [[TLD]]s to provide a fixed starting point for queries, and the need for [[SLD]]s to be unique. This, in turn, would necessitate  the need for a [[registrar]] type of administration, and help the nascent [[IT]] community recognize that the distribution of responsibility for each domain to individual name servers would provide administrative advantages.<ref>[http://www.livinginternet.com/i/iw_dns_history.htm Living Internet]</ref>

The need for a hierarchical [[DNS]] arose with the popularity of the Internet in academic spheres in the early 1980s, which eventually necessitated a de-centralized Internet. Communications between [[The Stanford Research Institute NIC]] and other institutions included plans to create a hierarchical [[DNS]], found in  [http://www.rfc-editor.org/rfc/rfc805.txt RFC 805], a group document from 1982. This document  outlines many of the basics of the eventual [[DNS]], including the need for [[TLD]]s to provide a fixed starting point for queries, and the need for [[SLD]]s to be unique. This, in turn, would necessitate  the need for a [[registrar]] type of administration, and help the nascent [[IT]] community recognize that the distribution of responsibility for each domain to individual name servers would provide administrative advantages.<ref>[http://www.livinginternet.com/i/iw_dns_history.htm Living Internet]</ref>

==Varieties of TLDs==

==Varieties of TLDs==

* Operating Mode

* Operating Mode

**Open - Operating and offering both registration and resolution services.

**Open - Operating and offering both registration and resolution services.

**Closed - Not Accepting registrations, may be resolving evergreen/legacy/infrastructure subdomains.

**Closed - Not accepting registrations, may be resolving evergreen/legacy/infrastructure subdomains.

* Level of Restriction

* Level of Restriction

**Unrestricted - If there are no requirements that must be met in order to register a name under a TLD, that TLD is Unrestricted.

**Unrestricted - If there are no requirements that must be met in order to register a name under a TLD, that TLD is Unrestricted.