Implementing WINS

Name Resolution Services

Name Release

When a computer finishes using a particular name, it no longer challenges other registration requests for the name. This is referred to as releasing a name.

If WINS is enabled on the client:￿Whenever a computer is shut down properly, it releases its name to the WINS server, which changes the state of the related database entry from active to released. If the entry remains released for a certain period of time, the WINS server marks it as extinct, updates the version number, and notifies other WINS servers of the change.

If a name is marked released at a WINS server, and a new registration arrives using that name but a different address, the WINS server immediately can give that name to the requesting client because it knows that the old client no longer is using that name. This might happen, for example, when a DHCP-enabled laptop changes subnets.

If the computer released its name during an orderly shutdown, the WINS server does not challenge the name when the computer is reconnected. If an orderly shutdown did not occur, the name registration with a new address causes the WINS server to challenge the registration. The challenge fails and the registration succeeds, because the computer no longer has the old address.

If WINS is not enabled on the client:￿When a non-WINS computer releases a name, a broadcast is made to allow any systems on the network that might have cached the name to remove it. Upon receiving name query packets specifying the deleted name, computers simply ignore the request, allowing other computers on the network to acquire the released name.

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For non-WINS computers to be accessible from other subnets, their names must be added as static entries to the WINS database or in the LMHOSTS / names.cfg file(s) on the remote system(s) because they will respond only to name queries that originate on their local subnet.

Name Resolution

With WINS servers in place on the internetwork, NetBIOS computer names are resolved using two basic methods depending on whether WINS resolution is available and enabled on the client computer. Regardless of which name resolution method is used, the process is transparent to the user after the system is configured.

Product Manual

U7613-J-Z815-6-76

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Siemens V4.0 manual Name Release, Name Resolution