dns - Computer Definition
- Domain Name System.The naming convention that divides the Internet into logical domains identified in Internet Protocol version 4 (IPv4) as a 32-bit portion of the total address.The standard convention is firstname.lastname@example.org, where user is the name of the end user, organization is the name of the enterprise or other organization owning or sponsoring the address, and domain is the type of entity owning or sponsoring the address.The administration of the DNS is the responsibility of Internet Corporation for Assigned Names and Numbers (ICANN). See also domain, ICANN, Internet, and IPv4.
- Domain Name Server. All Internet domain names are maintained in mirrored databases on root servers distributed around the world. These servers are updated by the domain registrars. Thousands of Domain Name Resolvers (DNRs) located strategically with Internet Service Providers (ISPs) and institutional networks periodically download database updates from the root servers. See also database, DNR, Internet, ISP, root, and server.
(Domain Name System) The Internet's system for converting alphabetic names into numeric IP addresses. For example, when a Web address (URL) is typed into a browser, DNS servers return the IP address of the Web server associated with that name. In this made-up example, the DNS converts the URL www.company.com into the IP address 220.127.116.11. Without DNS, you would have to type the series of four numbers and dots into your browser to retrieve the Web site, which you actually can do. See IP address. A Hierarchy of Servers The DNS system is a hierarchy of duplicated database servers worldwide that begin with the "root servers" for the top-level domains (.com, .net, .org, etc.). The root servers point to the "authoritative" servers located in ISPs, as well as in large companies, that turn the names into IP addresses; the process known as "name resolution." Using our www.company.com example, COMPANY.COM is the domain name, and WWW is the hostname. The domain name is the organization's identity on the Web, and the hostname is the name of the Web server within that domain (see WWW). See DNS records, zone file, reverse DNS, recursive DNS, DDNS, HOSTS file, mDNS, ping, root server and WINS.