Just some added stuff.
According to Microsoft TCP/IP Core Networking Guide, Chapter 7 page 493
B-node:
Uses IP broadcast meassage to register and resole NetBIOS names to IP-addresses. Windows 2000-based computers can use modifed B-node name resolution
P-node:
Uses point to point communcations with a NetBIOS name server (in Windows 2000-based networks, this is the WINS server) to register and resolve computers name to IP addresses.
M-node:
Uses a mix of B-node and P-node commucations to register and resolve NetBIOS names. Mnode first uses broadcast resolution; then, if necessary, it uses a server query
H-node:
Uses a hybrid of B-node and P-node. an H-node computer always tries a server query first and uses broadcast only if direct quiers fail. Windows 2000-based computers are configured to use hnode by defaul. to reduce IP broadcast, these computers use an LMHOSTS file to search for name to IP address mappings before using B-node IP broadcasts.
NOTE that using P-node the client will not resort to broadcasting according to MS. but there is a draw back that if your network is large and the server lives far away from the client; the client my never resolve a Netbios name to IP address, and then you allso have problems where name does not get unregistered or updated. the client only tries 3 times and then fails and does no more in P-node.