|
|
|
|
Domain Name Services BackgroundIP addresses uniquely identify every computer on the Internet. However, most people have difficulty memorizing long numeric strings.
In addition, computers are frequently assigned new IP addresses as they are relocated on a network. Thus, IP addresses cannot be used
reliably to locate computers over time.
To make it easier for users to access and remember the names of hosts on the Internet, a system was developed to allow networks and
hosts to be addressed using common-language names as well as IP addresses. This system is called the Domain Name Service (DNS).
Through DNS, each computer actually has two addresses--a numeric IP address and a host name. Either address can be used to connect to
or send information to the specified computer, though users most prefer to use the easier-to-remember host name.
It is important to remember that DNS is simply a convenience for humans; computers still must route packets of information by using the
IP address, not the host name. So for the system to work, there must be a way for the computers routing packets on the Internet to
translate the host names entered by human users into the IP addresses needed by computers on the Internet.
DNS performs this translation using a database of host information--computer files that match IP addresses to the proper host names.
Under this system, each site is considered a domain, organized under a hierarchy that groups similar domains together. Each domain provides
individually for name and addressing information about the hosts within the domain.
Other DNS resources: |
|
