A top-level domain (TLD) is one of the domains A domain name is an identification label that defines a realm of administrative autonomy, authority, or control on the Internet, based on the Domain Name System at the highest level in the hierarchical Domain Name System The Domain Name System is a hierarchical naming system for computers, services, or any resource connected to the Internet or a private network. It associates various information with domain names assigned to each of the participants. Most importantly, it translates domain names meaningful to humans into the numerical (binary) identifiers of the Internet The Internet is a global system of interconnected computer networks that use the standard Internet Protocol Suite to serve billions of users worldwide. It is a network of networks that consists of millions of private, public, academic, business, and government networks of local to global scope that are linked by a broad array of electronic and. The top-level domain names are installed in the root zone A DNS root zone is the top-level DNS zone in a Domain Name System hierarchy. Most commonly it refers to the root zone of the largest global DNS, deployed for the Internet. The zone is managed by the Internet Assigned Numbers Authority (IANA), managed by ICANN of the name space. For all domains in lower levels, it is the last part of the domain name A domain name is an identification label that defines a realm of administrative autonomy, authority, or control on the Internet, based on the Domain Name System, that is, the last label of a fully qualified domain name A fully qualified domain name , sometimes referred to as an absolute domain name, is a domain name that specifies its exact location in the tree hierarchy of the Domain Name System (DNS). It specifies all domain levels, including the top-level domain, relative to the root domain. A fully qualified domain name is distinguished by this absoluteness. For example, in the domain name www.example.com, the top-level domain is com The domain name com is a generic top-level domain in the Domain Name System of the Internet. Its name is derived from commercial, indicating its original intended purpose for networks of general commercial character, or COM, as domain names are not case-sensitive Text sometimes exhibits case sensitivity; that is, words can differ in meaning based on differing use of uppercase and lowercase letters. Words with capital letters do not always have the same meaning when written with lowercase letters. For example, Bill is the first name of former U.S. president William Clinton, who could sign a bill . And a. Management of most top-level domains is delegated to responsible organizations by the Internet Corporation for Assigned Names and Numbers ICANN is the Internet Corporation for Assigned Names and Numbers. Headquartered in Marina Del Rey, California, United States, ICANN is a non-profit corporation created on September 18, 1998, and incorporated on September 30, 1998 to be able to oversee a number of Internet-related tasks previously performed directly on behalf of the U.S. government (ICANN), which operates the Internet Assigned Numbers Authority The Internet Assigned Numbers Authority is the entity that oversees global IP address allocation, root zone management for the Domain Name System (DNS), media types, and other Internet Protocol related assignments. It is operated by the Internet Corporation for Assigned Names and Numbers, better known as ICANN (IANA) and is in charge of maintaining the DNS root zone A DNS root zone is the top-level DNS zone in a Domain Name System hierarchy. Most commonly it refers to the root zone of the largest global DNS, deployed for the Internet. The zone is managed by the Internet Assigned Numbers Authority (IANA), managed by ICANN.
Originally, the top-level domain space was organized into three main groups,[1] Countries, Categories, and Multiorganizations. An additional temporary group consisted only of the initial DNS domain,[2] arpa The domain name .arpa is a top-level domain in the Domain Name System of the Internet. It is used exclusively for technical infrastructure purposes. While the name originally was the acronym for the Advanced Research Projects Agency (ARPA), the funding organization in the United States that developed the precursor of the Internet (ARPANET), it now, intended for transitional purposes toward the stabilization of the domain name system.
Countries are designated in the Domain Name System by their two-letter ISO country code ISO 3166-1 alpha-2 codes are two-letter country codes defined in ISO 3166-1, part of the ISO 3166 standard published by the International Organization for Standardization , to represent countries, dependent territories, and special areas of geographical interest. They are the most widely used of the country codes published by ISO (the others being;[3] there are exceptions, however (e.g., .uk .uk is the Internet country code top-level domain for the United Kingdom. As of April 2010, it is the fourth most popular top-level domain worldwide (after .com, .de and .net), with over 8.48 million registrations). This group of domains is therefore commonly known as country-code top-level domains A country code top-level domain is an Internet top-level domain generally used or reserved for a country (a sovereign state or a dependent territory) (ccTLD).
The Categories group has become known as the generic top-level domains A generic top-level domain is one of the categories of top-level domains (TLDs) maintained by the Internet Assigned Numbers Authority (IANA) for use in the Domain Name System of the Internet. Initially this group consisted of GOV The domain name .gov is a sponsored top-level domain in the Domain Name System of the Internet. The name is derived from government, indicating its restricted use by government entities in the United States. The gov domain is administered by the General Services Administration (GSA), an independent agency of the United States federal government, EDU The domain name .edu is a sponsored top-level domain in the Domain Name System of the Internet. Its name is derived from education, indicating its intended use as a name space for educational institutions, primarily those in the United States. Although not officially mandated for much of the domain's existence, in practice it has been used, COM The domain name com is a generic top-level domain in the Domain Name System of the Internet. Its name is derived from commercial, indicating its original intended purpose for networks of general commercial character, MIL The domain name .mil is the sponsored top-level domain in the Domain Name System of the Internet for the United States Department of Defense and its subsidiary or affiliated organizations. The name is derived from military. It was one of the first top-level domains, created in January 1985, ORG The domain name org is a generic top-level domain of the Domain Name System (DNS) used in the Internet. The name is derived from organization, and NET The domain name net is a generic top-level domain used in the Domain Name System of the Internet. The name is derived from network, indicating its originally intended purpose for organizations involved in networking technologies, such as Internet service providers and other infrastructure companies. However, restrictions were never enforced and.
In the growth of the Internet, it became desirable to create additional generic top-level domains. Some of the initial domains' purposes were also generalized, modified, or assigned for maintenance to special organizations affiliated with the intended purpose.
As a result, IANA today distinguishes the following groups of top-level domains:[4]
- country-code top-level domains A country code top-level domain is an Internet top-level domain generally used or reserved for a country (a sovereign state or a dependent territory) (ccTLD): Two letter domains established for countries In geography, a country is a geographical region. The term is often applied to a political division or the territory of a sovereign state, or to a smaller, or former, political division of a geographical region. Usually, but not always, a country coincides with a sovereign territory and is associated with a state, nation or government or territories A dependent territory, dependent area or dependency is a territory that does not possess full political independence or sovereignty as a State or their internationalized domain names An internationalized domain name is an Internet domain name that contains at least one label that is displayed in software applications, in whole or in part, in a language-specific script or alphabet, such as Chinese, Russian or the Latin alphabet-based characters with diacritics, such as French. These writing systems are encoded by computers in (IDN ccTLD). With some historical exceptions, the code for any territory is the same as its two-letter ISO 3166 ISO 3166 is a standard published by the International Organization for Standardization , and defines codes for the names of countries, dependent territories, and special areas of geographical interest, and their principal subdivisions (e.g., provinces or states). The official name of the standard is Codes for the representation of names of code.
- generic top-level domains A generic top-level domain is one of the categories of top-level domains (TLDs) maintained by the Internet Assigned Numbers Authority (IANA) for use in the Domain Name System of the Internet (gTLD): Top-level domains with three or more characters
- unsponsored top-level domains: domains that operate directly under policies established by ICANN processes for the global Internet community.
- sponsored top-level domains A sponsored top-level domain is one of the categories of top-level domains (TLDs) maintained by the Internet Assigned Numbers Authority (IANA) for use in the Domain Name System of the Internet (sTLD): These domains are proposed and sponsored by private agencies or organizations that establish and enforce rules restricting the eligibility to use the TLD. Use is based on community theme concepts.
- infrastructure top-level domain: This group consists of one domain, the Address and Routing Parameter Area The domain name .arpa is a top-level domain in the Domain Name System of the Internet. It is used exclusively for technical infrastructure purposes. While the name originally was the acronym for the Advanced Research Projects Agency (ARPA), the funding organization in the United States that developed the precursor of the Internet (ARPANET), it now (ARPA). It is managed by IANA on behalf of the Internet Engineering Task Force The Internet Engineering Task Force develops and promotes Internet standards, cooperating closely with the W3C and ISO/IEC standards bodies and dealing in particular with standards of the TCP/IP and Internet protocol suite. It is an open standards organization, with no formal membership or membership requirements. All participants and managers are for various purposes specified in Request for Comments In computer network engineering, a Request for Comments is a memorandum published by the Internet Engineering Task Force (IETF) describing methods, behaviors, research, or innovations applicable to the working of the Internet and Internet-connected systems.
In addition, a group of internationalized domain name An internationalized domain name is an Internet domain name that contains at least one label that is displayed in software applications, in whole or in part, in a language-specific script or alphabet, such as Chinese, Russian or the Latin alphabet-based characters with diacritics, such as French. These writing systems are encoded by computers in (IDN) top-level domains has been installed under test test is a name reserved by the Internet Engineering Task Force in RFC 2606 (June 1999) that is not intended to be installed as a top-level domain (TLD) in the global Domain Name System (DNS) of the Internet for production use for testing purposes. Since November 2009, countries and territories may apply for IDN ccTLDs In the Internet Domain Name System, an internationalized country code top-level domain or IDN ccTLD is a country code top-level domain that employs a non Latin alphabet, such as Arabic or Cyrillic. As of May 2010[update] there are four such TLDs: مصر., السعودية. and امارات. (for Egypt, Saudi Arabia and the United.
The authoritative list of currently existing TLDs The official list of all top-level domains is maintained by the Internet Assigned Numbers Authority in the root zone is published at the IANA website at http://www.iana.org/domains/root/db/.
Contents |
Internationalized country code TLDs
Main article: Internationalized country code TLDAn internationalized country code top-level domain is a country code top-level domain in a non Latin alphabet, such as Arabic. As of May 2010[update] there are four such TLDs: مصر., السعودية. and امارات. (for Egypt Egypt (pronounced /ˈiːdʒɪpt/ ; Arabic: مصر Miṣr, pronounced [misˤɾ] ( listen); Arabic: مِصْر Miṣr [ˈmisˤɾ]; Egyptian Arabic: مَصْر Maṣr [ˈmɑsˤɾ]; Coptic: Ⲭⲏⲙⲓ, kīmi; Egyptian: 𓆎𓅓𓏏𓊖 Kemet), officially the Arab Republic of Egypt, is a country mainly in North Africa, with the Sinai Peninsula, Saudi Arabia Saudi Arabia (Arabic: المملكه العربيه السعوديه) is the largest Arab country of the Middle East. It is bordered by Jordan and Iraq on the north and northeast, Kuwait, Qatar, Bahrain and the United Arab Emirates on the east, Oman on the southeast, and Yemen on the south. The Persian Gulf lies to the northeast and the Red Sea and the United Arab Emirates The United Arab Emirates (Arabic: دولة الإمارات العربية المتحدة, Dawlat al-Imārāt al-‘Arabīyah al-Muttaḥidah, short-name:The Emirates, local short-name:Al Emarat الامارات) is a federation of seven emirates situated in the southeast of the Arabian Peninsula in Southwest Asia on the Persian Gulf, bordering respectively), and .рф (for Russia Russia (pronounced /ˈrʌʃə/ ; Russian: Россия, tr. Rossiya, pronounced [rɐˈsʲijə] ( listen)), also officially known as the Russian Federation (Russian: Российская Федерация, tr. Rossiyskaya Federatsiya, pronounced [rɐˈsʲijskəjə fʲɪdʲɪˈraʦəjə] ( listen)), is a country in northern Eurasia. It is a federal)
Infrastructure domain
The domain arpa The domain name .arpa is a top-level domain in the Domain Name System of the Internet. It is used exclusively for technical infrastructure purposes. While the name originally was the acronym for the Advanced Research Projects Agency (ARPA), the funding organization in the United States that developed the precursor of the Internet (ARPANET), it now was the first Internet top-level domain. It was intended to be used only temporarily, aiding in the transition of traditional ARPANET host names to the domain name system. However, after it had been used for reverse DNS lookup In computer networking, reverse DNS lookup or reverse DNS resolution is the determination of a domain name that is associated with a given IP address using the Domain Name System (DNS) of the Internet, it was found impractical to retire it, and is used today exclusively for Internet infrastructure purposes such as in-addr.arpa for IPv4 and ip6.arpa for IPv6 reverse DNS resolution, uri.arpa and urn.arpa for the Dynamic Delegation Discovery System Defined in RFC 3401, RFC 3402, RFC 3403, RFC 3404, and RFC 3405, and e164.arpa for telephone number mapping Telephone number mapping is the process of unifying the telephone number system of the public switched telephone network with the Internet addressing and identification name spaces. Telephone numbers are systematically organized in the E.164 standard, while the Internet uses the Domain Name System for linking domain names to IP addresses and other based on NAPTR DNS records A Name Authority Pointer is a type of resource record used in the Domain Name System (DNS). For historical reasons, arpa The domain name .arpa is a top-level domain in the Domain Name System of the Internet. It is used exclusively for technical infrastructure purposes. While the name originally was the acronym for the Advanced Research Projects Agency (ARPA), the funding organization in the United States that developed the precursor of the Internet (ARPANET), it now is sometimes considered to be a generic top-level domain.
Reserved domains
RFC 2606 reserves the following four top-level domain names to avoid confusion and conflict.[5] They may be used for various specific purposes however, with the intention that these should not occur in production networks within the global domain name system:
- example example is a name reserved by the Internet Engineering Task Force in RFC 2606 (June 1999) that is not intended to be installed as a top-level domain in the global Domain Name System (DNS) of the Internet: reserved for use in examples
- invalid invalid is a name reserved by the Internet Engineering Task Force in RFC 2606 (June 1999) that is not intended to be installed as a top-level domain in the global Domain Name System (DNS) of the Internet: reserved for use in obviously invalid domain names
- localhost localhost is a name reserved by the Internet Engineering Task Force in RFC 2606 (June 1999) that is not intended to be installed as a top-level domain in the global Domain Name System (DNS) of the Internet: reserved to avoid conflict with the traditional use of localhost In computer networking, localhost is the standard hostname given to the address of the loopback network interface. The name is also a reserved domain name (cf. .localhost), set aside to avoid confusion with the narrower definition as a hostname as a hostname
- test: reserved for use in tests
The test domain has seen usage by ICANN in the testing of internationalized domain names, a program started in 2007.[6][7]
- xn—kgbechtv Arabic (إختبار)
- xn—hgbk6aj7f53bba Persian (آزمایشی)
- xn—0zwm56d Chinese, simplified (测试)
- xn—g6w251d Chinese, traditional (測試)
- xn—80akhbyknj4f Cyrillic (испытание)
- xn—11b5bs3a9aj6g Hindi (परीक्षा)
- xn—jxalpdlp Greek (δοκιμή)
- xn—9t4b11yi5a Korean (테스트)
- xn—deba0ad Yiddish, Hebrew (טעסט)
- xn—zckzah Japanese (テスト)
- xn—hlcj6aya9esc7a Tamil (பரிட்சை)
Historical domains
In the late 1980s InterNIC created the nato domain for use by NATO. NATO considered none of the then existing TLDs as adequately reflecting their status as an international organization. Soon after this addition, however, InterNIC also created the int TLD for the use by international organizations in general, and persuaded NATO to use the second level domain nato.int instead. The nato TLD, no longer used, was finally removed in July 1996.
Other historical TLDs are cs for Czechoslovakia (now cz for Czech Republic and sk for Slovak Republic), dd for East Germany (using de after reunification of Germany), yu for SFR Yugoslavia (now: ba for Bosnia and Herzegovina, hr for Croatia, me for Montenegro, mk for Macedonia, rs for Serbia and si for Slovenia), and zr for Zaire (now cd for Democratic Republic of the Congo). In contrast to these, the TLD su has remained active despite the demise of the Soviet Union that it represents.
Proposed domains
Further information: Proposed top-level domainAbout the time[when?] that ICANN discussed and finally introduced[8] aero, biz, coop, info, museum, name, and pro TLDs, site owners argued that a similar TLD should be made available for adult and pornographic websites to settle the dispute of obscene content on the Internet and the responsibility of service providers under the Communications Decency Act of 1996. Several options were proposed including xxx, sex and adult, but ICANN has not created any.[9]
An older proposal[10] consisted of seven new gTLDs: arts, firm, info, nom, rec, shop, and web. Later biz, info, museum, and name covered most of these old proposals.
During the 32nd International Public ICANN Meeting in Paris in 2008,[11] ICANN started a new process of TLD naming policy to take a "significant step forward on the introduction of new generic top-level domains." This program envisions the availability of many new or already proposed domains, as well a new application and implementation process.[12] Observers believed that the new rules could result in hundreds of new gTLDs to be registered.[13] Proposed TLDs include music, shop, berlin, wine and nyc.
Alternative DNS roots
Further information: Alternative DNS rootICANN's slow progress in creating new generic top-level domains, and the high application costs associated with TLDs, contributed to the creation of alternate DNS roots with different sets of top-level domains. Such domains may be accessed by configuration of a computer with alternate or additional (forwarder) DNS servers or plugin modules for web browsers. Browser plugins detect alternate root domain requests and access an alternate domain name server for such requests.
Pseudo-domains
Several networks, such as BITNET, CSNET, UUCP or other networks, existed that were in widespread use among computer professionals and academic users, that were incompatible with the Internet and exchanged e-mail with the Internet via special e-mail gateways. For relaying purposes on the gateways, messages associated with these networks were labeled with suffixes such as bitnet, oz, csnet, or uucp, but these domains did not exist as top-level domains in the public Domain Name System of the Internet.
Most of these networks have long since ceased to exist, and although UUCP still gets significant use in parts of the world where Internet infrastructure has not yet become well-established, it subsequently transitioned to using Internet domain names, so pseudo-domains now largely survive as historical relics. One notable exception is the 2007 emergence of SWIFTNet Mail, which uses the swift pseudo-domain.[14]
The top-level pseudo domain local is required by the Zeroconf protocol. It is also used by many organizations internally, which may become a problem for those users as Zeroconf becomes more popular. Both site and internal have been suggested for private usage, but no consensus has emerged[citation needed].
The anonymity network Tor has a top-level pseudo-domain onion, which can only be reached with a Tor client because it uses the Tor-protocol (onion routing) to reach the hidden service to protect the anonymity of users.
See also
References
- ^ RFC 920, Domain Requirements, J. Postel, J. Reynolds, The Internet Society (October 1984)
- ^ RFC 921, Domain Name System Implementation Schedule - Revised, J. Postel, The Internet Society (October 1984)
- ^ Codes for the Representation of Names of Countries, ISO-3166, International Organization for Standardization. (May 1981)
- ^ IANA root zone database
- ^ RFC 2606 (BCP 32), Reserved Top Level DNS Names, D. Eastlake, A. Panitz, The Internet Society (June 1999)
- ^ ICANN IDN wiki
- ^ IANA (ICANN) list of extant TLDs
- ^ InterNIC FAQs on New Top-Level Domains
- ^ RFC 3675: .sex Considered Dangerous
- ^ (historical) gTLD MoU
- ^ "32nd International Public ICANN Meeting". ICANN. 22 June 2008. http://par.icann.org/.
- ^ "New gTLD Program". ICANN. http://www.icann.org/en/topics/new-gtld-program.htm. Retrieved 15 June 2009.
- ^ ICANN Board Approves Sweeping Overhaul of Top-level Domains, CircleID, 26 June 2008.
- ^ "SWIFTNet Mail now available". SWIFT. 16 May 2007. http://www.swift.com/about_swift/press_room/swift_news_archive/home_page_stories_archive_2007/mail_now_available.page. Retrieved 3 January 2010.
- Addressing the World: National Identity and Internet Country Code Domains, edited by Erica Schlesinger Wass (Rowman & Littlefield, 2003, ISBN 0-7425-2810-3) [1], examines connections between cultures and their ccTLDs.
- Ruling the Root by Milton Mueller (MIT Press, 2001, ISBN 0-262-13412-8) [2], discusses TLDs and domain name policy more generally.
- RFC 1591 - Domain Name System Structure and Delegation
- RFC 3071 - Reflections on the DNS, RFC 1591, and Categories of Domains
External links
- Articles on CircleID about TLDs
- IANA TLD List
- "Top-Level Domain Names by Host Count". ISC. January 2008. http://ftp.isc.org/www/survey/reports/current/report.bynum. Retrieved 7 August 2008.
|
|||||||||||||||||||||||||||||||||||||||||||||||||
Categories: Domain name system | Internet governance | Top-level domains | Identifiers
|
Wed, 07 Jul 2010 16:33:22 GMT+00:00
Telephony World (press release) .SE is responsible for the Internet's Swedish top-level domain , .se, encompassing domain name registration and administration, as well as the technical ...
admin
Sat, 24 Jul 2010 16:21:12 GM
You should build one and get your own . top level domain. . Having a top level dot com domain will make your site very professional so that online buyers will trust you. Build a website with useful content but of course do not forget to ...
Q. is there such a thing as .jobs top level domain?
Asked by Michael M - Fri Aug 24 10:59:45 2007 - - 1 Answers - 0 Comments
A. Yes. "The .jobs domain is reserved for human resource managers and is sponsored by Employ Media LLC."
Answered by metalicurt - Fri Aug 24 11:10:40 2007
