WINS Proxy

A WINS proxy is a WINS-enabled computer that helps resolve name queries for non-WINS enabled computers in routed TCP/IP intranets. By default, non-WINS enabled computers are configured as b-node, which uses IP broadcasts for name queries. The WINS proxy computer listens on the local subnet for IP broadcast name queries.

When a non-WINS enabled computer sends an IP name query broadcast, the WINS proxy accepts the broadcast and checks its cache for the appropriate NetBIOS computer name-to-IP-address mapping. If the WINS proxy has the correct mapping in its cache, the WINS proxy sends this information to the non-WINS computer. If the name-to-IP-address mapping is not in cache, the WINS proxy queries a WINS server for the name-to-IP-address mapping.

If a WINS server is not available on the local subnet, the WINS proxy can query a WINS server across a router. The WINS proxy caches (stores in memory) computer name-to-IP-address mappings it receives from the WINS server. These mappings are used to respond to subsequent IP broadcast name queries from b-node computers on the local subnet.

The name-to-IP-address mappings that the WINS proxy receives from the WINS server are stored in the WINS proxy cache for a limited time. (By installation default, this value is six minutes. The minimum value is one minute.)

When the WINS proxy receives a response from the WINS server, it stores the mapping in its cache and responds to any subsequent name query broadcasts with the mapping received from the WINS server.

The role of the WINS proxy is similar to that of the DHCP/BOOTP relay agent, which forwards DHCP client requests across routers. Because the WINS server does not respond to broadcasts, a computer configured as a WINS proxy should be installed on subnets that include computers that use broadcasts for name resolution.

To configure a Windows NT, Version 4.0, computer as a WINS proxy, you must manually edit that computer's registry. The EnableProxy keyword must be set to 1 (REG_DWORD). This keyword is located in the following key: HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Netbt\Parameters