Section 3.3: Name Resolution

Windows XP Professional supports the use of user-friendly domain names to represent the IP address of a host or a client. This however requires name resolution so that the computer can identify the IP address that the user-friendly name refers to. Windows XP Professional supports two types of name resolution: NetBIOS name resolution and host name resolution.

3.3.1: NetBIOS Name Resolution

Although Microsoft has phased out NetBIOS name resolution, it remains in Windows XP Professional for compatibility purposes. Two of the mechanisms implemented for NetBIOS name resolution are Windows Internet Naming Service (WINS), which is a NetBIOS name server that stores NetBIOS names and their IP Addresses; and the LmHOSTS file, which is a static text file that contains a list of NetBIOS names and their corresponding IP addresses and is stored on the local computer.

3.3.2: Host Name Resolution

Windows XP Professional uses Domain Name Services (DNS) to resolve host names. DNS name servers resolve forward and reverse lookup queries. A forward lookup query resolves a user-friendly domain name to an IP address. A reverse lookup query resolves an IP address to a user-friendly domain name. A name server can resolve a query only for a zone for which it has authority. If a name server cannot resolve the query, it passes the query to other name servers that can resolve the query. The name server caches the query results to reduce the DNS traffic on the network.

DNS Zones

DNS uses domain name space is the naming. The DNS database is indexed by name; therefore, each domain must have a name. As you add domains to the hierarchy, the name of the parent domain is appended to its child domain. Consequently, a domain's name identifies its position in the hierarchy. Thus the domain name identities the studyguides domain as a child domain or subdomain of the domain and testking as a subdomain of the com domain. A discrete portion of the domain name space is represented as a zone. Zones provide a way to partition the domain name space into manageable sections.