Domain Name System (DNS) – Resolves Internet names to IP addresses.
The Domain Name System (DNS) provides a way for hosts to use this name to request the IP address of a specific server, as shown in the figure. DNS names are registered and organized on the Internet within specific high-level groups, or domains. Some of the most common high-level domains on the Internet are .com, .edu, and .net.
Translating Domain Names to IP Addresses
Computer names are easier for users to understand than IP addresses. Name Resolution translates IP addresses to computer names to ensure simplification of IP address identification. Instead of using the 32-bit IP addresses, name resolution assigns computer names to the IP addresses of the destination hosts.
Thousands of servers, installed in many different locations, provide the services we use daily over the Internet. Each of these servers is assigned a unique IP address that identifies it on the local network where it is connected.
Without realizing it, by using the internet, we use DNS (Domain Name System). DNS is a protocol within the TCP/IP protocol suite, which is responsible for transferring information between devices within the network. DNS is essentially a GPS for a computer. DNS converts a domain name to an Internet Protocol (IP) address.
Another important concept in Name Resolution is FQDN, which stands for Fully Qualified Domain Name. FQDN is the complete domain name for a specific device on the internet. FQDN consists of two parts: the hostname and the domain name. Example: mymail.somecompany.com is the FQDN for a hypothetical company. The hostname is “mymail.” The host is located within the domain “somecompany.com.”
Domain Name Server (DNS) – Service that provides the IP address of a web site or domain name so a host can connect to it
It would be impossible to remember all of the IP addresses for all of the servers hosting services on the Internet. Instead, there is an easier way to locate servers by associating a name with an IP address.