Implementing WINS

Name Resolution Services

Defined within NetBT are modes which specify how network resources are identified and accessed. The most common NetBT modes are as follows:

b-node, which uses broadcast messages to resolve names.

p-node, which uses point-to-point communications with a name server to resolve names.

m-node, which first uses b-node and then—if necessary—p-node to resolve names.

h-node, which first uses p-node for name queries and then b-node if the name service is unavailable or if the name is not registered in the database.

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The RFCs refer to a NetBIOS Name Server (NBNS). WINS is an enhanced NBNS.

The two most common node types for Windows client computers are h-node and b-node.

For DHCP users, the node type is assigned by the DHCP server. When WINS servers are in place on the network, NetBT resolves names on a client computer by communicating with the WINS server. When WINS servers are not in place, NetBT uses b-node broadcast messages to resolve names. NetBT also can use LMHOSTS files for name resolution, depending on how TCP/IP is configured on a particular computer.

Advanced Server can respond to b-node and h-node NetBT modes. (Windows NT supports all of the NetBT modes.) Client computers can use the modes described in the following sections.

B-Node (Broadcast Node)

The b-node mode uses broadcasts for name registration and resolution. That is, if CLIENT_PC1 wants to communicate with CLIENT_PC2, it will broadcast to all machines that it is looking for CLIENT_PC2 and then will wait a specified time for CLIENT_PC2 to respond.

The b-node mode has two major problems:

In a large environment, it loads the network with broadcasts.

Typically, routers do not forward broadcasts, so computers that are on opposite sides of a router will never hear the requests.

P-Node (Point-to-Point Node)

The p-node mode addresses the issues that b-node does not solve. In a p-node environment, computers neither create nor respond to broadcasts. All computers register themselves with the WINS server, which is responsible for knowing computer names and addresses and for ensuring no duplicate names exist on the network.

Product Manual

U7613-J-Z815-6-76

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Siemens V4.0 manual Node Broadcast Node, Node Point-to-Point Node