WINS

The purpose of WINS is to allow a NetBIOS name to be converted to an IP address. Therefore computers using WINS must be using NBT (NetBIOS over TCP/IP). WINS was originally put in place to compensate for a shortcoming of NetBEUI which is the fact that it is not routable. Therefore on large Networks IP is used to transport NetBIOS and rather than using broadcasts, information is sent to the WINS server.

WINS converts Windows computer names to IP addresses but does not do name lookups based on IP addresses. The use of Windows Explorer or NET commands invokes the NetBIOS interface. NetBIOS names, if repeated on another domain that is on the network, may cause a problem since there is no way to distinguish NetBIOS names between two domains. Each computer, when booted, sends a name registration broadcast. If there is no response, the computer will use the name it registered. A NetBIOS broadcast releases the computer name when the computer is shutdown gracefully.

WINS reduces this broadcast traffic when using NBT. The registration and release is sent to the WINS server rather than being broadcast. The clients have the IP address of the WINS server and they are configured to use WINS before using NetBIOS broadcasts. A backup WINS server may be available on the network for fault tolerance.

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