DNS Name Resolution

So that people can reach your Web site on an intranet or the Internet, you must have a unique IP address that identifies your computer on the network. This address consists of a long string of numbers separated by dots, for example, 172.16.255.255. Because a numeric address is difficult for people to remember, text names, or friendly names, are used to provide visitors with an address that is easy to remember, such as www.microsoft.com. Name resolution involves supplying the correct numerical address from the friendly name that was typed into a client browser.

Name Resolution Systems

Windows networking components rely on the NetBIOS naming convention. In contrast, TCP/IP components rely on a naming convention known as the Domain Name System (DNS). Under Windows, the DNS host name of the server defaults to the same name as the NetBIOS computer name. The mapping of computer names to IP addresses can be accomplished using one of the following two methods:

Static—The system administrator creates either a text file for DNS names, called a HOSTS file, or an LMHOSTS file for NetBIOS names, and enters each computer's name and IP address. The file is then distributed on the network. When a request for a connection to another computer is made, the file is used to resolve the name to the correct IP address. This system works well for simple networks that change infrequently.
Dynamic—A distributed database of computer names and their associated IP addresses is maintained on DNS servers. When a DNS server receives a request for an address assigned to a specified DNS name, it attempts to locate the requested information by retrieving data from its portion of the database. If this fails because the server is not authoritative for the DNS domain requested and thus does not have the data for the requested domain, the server can check its cache, communicate with other DNS servers to resolve the request, or refer the client to another DNS server that might know the answer.

You can specify which DNS server or servers your server uses to resolve DNS names, or you can configure your server to obtain the address of a DNS server from a DHCP server. For more information, see see DNS Configuration.