The Domain Name System (or DNS) converts the Internet domain and host names into IP addresses. DNS by design translates the address a user enters into a web browser to the IP addresses of the servers where the site is situated. An address using the alphabet is much easier for a user to remember than a numerical IP address, so DNS is a vital system that was pivotal in bringing the Internet to the mass public.
DNS implements a database to retain this name and address information for every public host on the Internet. DNS works on the assumption that IP addresses are static rather than dynamic. The DNS database is kept on a system of database servers. When Web browsers issues a request involving Internet host names, software known as a DNS resolver (usually built into the network OS) is utilised. The software first contacts a DNS server to determine the server’s IP address. If the DNS server does not contain the required IP address, the request is forwarded to another DNS server. This process potentially repeats several times until the IP is given, which is then sent to the DNS resolver. The resolver translates the request over Internet Protocol and the web browser is finally able to view the site.
