Name Resolution

Name Resolution is the process by a character-based name, such as Mycomputer or http://www.microsoft.com, is translated into a numeric address, such as 192.168.1.1, that the protocol stack can recognize. This section describes the two TCP/IP-related name resolution protocols provided by Windows, Domain Name System (DNS) and Windows Internet Name Service (WINS).

Domain Name System

Domain Name System (DNS) is a standard by which Internet names (such as http://www.microsoft.com) are translated to their corresponding IP addresses. A network application that wants to resolve a DNS name to an IP address sends a DNS lookup request using the TCP/IP protocol to a DNS server. DNS servers implement a distributed database of name/IP address pairs that are used to perform translations, and each server maintains the translations for a particular zone. Describing the details of DNS is outside the scope of this book, but DNS is the foundation of naming in Windows and so it is the primary Windows name resolution protocol.

The Windows DNS server is implemented as a Windows service (\Windows\System32\ Dns.exe) that is included in server versions of Windows. Standard DNS server implementation relies on a text file as the translation database, but the Windows DNS server can be configured to store zone information in Active Directory.

Windows Internet Name Service

A networking service called Windows Internet Name Service (WINS) maintains the mapping between NetBIOS names and IP addresses used for NetBIOS-based TCP/IP applications. If WINS isn't installed, NetBIOS uses local broadcast messages for name operations on a subnet. Note that NetBIOS names are secondary to DNS names for Windows Sockets applications; computer names are registered and resolved first through DNS, with Windows falling back on NetBIOS names only if DNS name resolution fails.