A system and method for allowing remote callers to access a secure telephone network maintains a registry (i.e. a database) of all remote callers that have access to the network. The registry contains an electronic serial number (ESN) and a personal identification number (PIN) for each remote caller. The ESN is typically the serial number of the callers cellular telephone. Alternatively, the ESN is a phone number of the remote caller's telephone. To establish a connection, the remote caller calls a private branch exchange (PBX) of the secure network. Upon receiving the call, the PBX compares the ESN and PIN of the remote caller with the ESN and PIN stored in the registry. If a match is found, the PBX authenticates the remote caller and allows the connection. The remote caller may have full access or access limited by a connection policy.