The right to use a domain name is delegated by domain name registrars which are accredited by the Internet Corporation for Assigned Names and Numbers (ICANN), the organization charged with overseeing the name and number systems of the Internet. In addition to ICANN, each top-level domain (TLD) is maintained and serviced technically by a sponsoring organization, the TLD Registry. The registry is responsible for maintaining the database of names registered within the TLDs they administer. The registry receives registration information from each domain name registrar authorized to assign names in the corresponding TLD and publishes the information using a special service, the whois protocol.
Registrars usually charge an annual fee for the service of delegating a domain name to a user and providing a default set of name servers. Often this transaction is termed a sale or lease of the domain name, and the registrant is called an "owner", but no such legal relationship is actually associated with the transaction, only the exclusive right to use the domain name. More correctly authorized users are known as "registrants" or as "domain holders".
ICANN publishes a complete list of TLD registries and domain name registrars in the world. One can obtain information about the registrant of a domain name by looking in the WHOIS database held by many domain registries.
For most of the more than 240 country code top-level domains (ccTLDs), the domain registries hold the authoritative WHOIS (Registrant, name servers, expiration dates, etc.). For instance, DENIC, Germany NIC, holds the authoritative WHOIS to a .DE domain name. Since about 2001, most gTLD registries (.ORG, .BIZ, .INFO) have adopted this so-called "thick" registry approach, i.e. keeping the authoritative WHOIS in the central registries instead of the registrars.
For .COM and .NET domain names, a "thin" registry is used: the domain registry (e.g. VeriSign) holds a basic WHOIS (registrar and name servers, etc.). One can find the detailed WHOIS (registrant, name servers, expiry dates, etc.) at the registrars.
Some domain name registries, also called Network Information Centres (NIC), also function as registrars, and deal directly with end users. But most of the main ones, such as for .COM, .NET, .ORG, .INFO, etc., use a registry-registrar model. There are hundreds of Domain Name Registrars that actually perform the domain name registration with the end user (see lists at ICANN or VeriSign). By using this method of distribution, the registry only has to manage the relationship with the registrar, and the registrar maintains the relationship with the end users, or 'registrants' -- in some cases through additional layers of resellers.
Tuesday, September 9, 2008
Domain Name Registration
Domain Name - Details
The Domain Name System (DNS) is a hierarchical naming system for computers, services, or any resource participating in the Internet. It associates various information with domain names assigned to such participants. Most importantly, it translates humanly-meaningful domain names to the numerical (binary) identifiers associated with networking equipment for the purpose of locating and addressing these devices world-wide.
An often used analogy to explain the Domain Name System is that it serves as the "phone book" for the Internet by translating human-friendly computer hostnames into IP addresses. For example, www.example.com translates to 208.77.188.166.
The Domain Name System makes it possible to assign domain names to groups of Internet users in a meaningful way independent of each user's physical location. Because of this, World-Wide Web (WWW) hyperlinks and Internet contact information can remain consistent and constant even if the current Internet routing arrangements change or the participant uses a mobile device. Internet domain names are easier to remember than IP addresses such as 208.77.188.166 or 2001:db8:1f70::999:de8:7648:6e8. People take advantage of this when they recite meaningful URLs and e-mail addresses without caring how the machine will actually locate them.
The Domain Name System distributes the responsibility for assigning domain names and mapping them to Internet Protocol (IP) networks by designating authoritative name servers for each domain to keep track of their own changes, avoiding the need for a central register to be continually consulted and updated.
In general, the Domain Name System also stores other types of information, such as the list of mail servers that accept email for a given Internet domain. By providing a world-wide, distributed keyword-based redirection service, the Domain Name System is an essential component of the functionality of the Internet.
Other identifiers such as RFID tags, UPC codes, International characters in email addresses and host names, and a variety of other identifiers could all potentially utilize DNS [1].
The Domain Name System also defines the technical underpinnings of the functionality of this database service. For this purpose it defines the DNS protocol, a detailed specification of the data structures and communication exchanges used in DNS, as part of the Internet Protocol Suite (TCP/IP). The context of the DNS within the Internet protocols may be seen in the following diagram. The DNS protocol was developed and defined in the early 1980's and published by the Internet Engineering Task Force (cf. History).
