What DNS Does

• DNS servers act as telephone directories for the Internet. Each node on the Internet is assigned a unique IP address. Site names are assigned solely for user convenience. Much like making an entry in your phone’s personal directory, the name “Mom” means nothing without an associated phone number. When your browser sends a request to view a page at SomeWebSite.com, that site name is directed to a DNS server that matches the registered site name to the IP address registered for that site. Once the server matches the name and address, the request is forwarded to the proper destination host server.
  
  

Primary and Secondary

• As the names suggest, the primary DNS address is the first server your computer will send a request to. If the request times out or receives a bad response from the primary server, it is forwarded to the secondary DNS address. This fail-safe precaution lets you continue your normal Internet activities when one server fails or is taken out of service for maintenance.
  
  

Convenience

• Strictly speaking, DNS is not essential to gain access to websites. If you prefer to memorize the IP addresses for every website to want to visit, you can open the page directly by entering the address rather than the name of the site in your browser. Entering 74.125.73.104 in your browser’s address bar will take you to the Google search page just as quickly as entering Google.com. Most people find the latter easier to remember.
  
  

Administration

• The rules governing assignment of IP addresses and registration of domain names are established by the Internet Corporation for Assigned Names and Numbers, ICANN. This international, non-profit body charged with setting and enforcing standard procedures used to direct the massive amount of traffic transmitted on the Internet each day.
  
  

Domain Registration

• Registration of Internet domain names is overseen in the United States by InterNIC. This agency is charged with resolving disputes over contested domains, trademark infringement and other legal issues. Actual domain name registration is contracted to a number of accredited registrars throughout the world. A list of these is available on the InterNIC.net website.