| 摘要 |
A communication network is established by a connection to a user terminal that is capable of roaming amongst a plurality of serving areas. The network includes a controller for each serving area capable of routing a connection to a location covered by that serving area. If a controller serving the user terminal is faulty, a home database, which stores a plurality of identities of other controllers, is able to route the connection to the user terminal by selecting one of the other controllers that is valid. |
