Patent ID: 7298708

Claim:
A method of registering an IP device programmed for a particular PBX in a network of multiple PBXs connected in clusters, said PBXs including respective servers and controllers, where one of said servers has provided to the IP device an IP address for one of said controllers in a further PBX for which the IP device has not been programmed, the method comprising: receiving a software ID from said IP device and in response accessing a database to obtain a further IP address for a designated controller in said particular PBX for which the IP device has been programmed, and redirecting said IP device to establish a connection with said designated controller for registering said IP device therewith; wherein said accessing said database includes reading a first ID from said database using said software ID as a key to identify one of said clusters within said network containing said designated controller; reading a second ID from said database using said first ID as a key to identify one of said multiple PBXs within said one of said clusters containing said designated controller; and reading said further IP address for said designated controller from said database using said second ID as a key.