A NetBIOS name resolution method used for name registration and resolution. P-node is one of the types of NetBIOS over TCP/IP nodes defined in Request for Comments (RFC) numbers 1001 and 1002, and is supported by computers running Microsoft Windows NT and Windows 2000.
Name resolution is the process of converting the name of a host on the network into a network address (such as an IP address). Name resolution must be performed to establish communication over a network. P-node is one of four basic methods supported by Windows NT for resolving NetBIOS host names (that is, computer names) into IP addresses.
If a computer running Windows NT is configured as a P-node machine, it does not use broadcasts to resolve the names of the hosts. Instead, it tries to query a NetBIOS name server to resolve names of other hosts on the network. The advantage of doing this is that name resolution can function across large internetworks consisting of IP subnets connected with routers. Routers normally block broadcasts but will forward packets directed toward a specific name server.
A server running the Windows Internet Naming Service (WINS) is a typical example of a NetBIOS name server. If the WINS server is unavailable to the client issuing the query, the requested name cannot be resolved into its associated IP address. Furthermore, each client must be configured with the IP address of the WINS server in order for P-node name resolution to work. For this reason, M-node or H-node methods are usually preferred; they can use both broadcasts and directed traffic to resolve NetBIOS names of hosts.