Patent ID: 7289818

Claim:
A method comprising: synchronizing subscriber information databases over a network with respect to subscriber information of each subscriber registered among a plurality of wireless network systems in a multi-zone arrangement; and upon a Short Message Service (SMS) transmission request signal from a first terminal to at least one second terminal being received, forming data packets of an SMS message in accordance with the received SMS transmission request signal, and retrieving the synchronized subscriber information database to send the formed SMS data packets over the network to a wireless network system corresponding to current position information of the at least one second terminal; wherein synchronizing subscriber information databases comprises: a first synchronization to synchronize the subscriber information between Home Location Registers (HLRs) of the wireless network systems in the multi-zone arrangement over the network; and a second synchronization step to synchronize the subscriber information between SMS databases of SMS servers in associated wireless network systems where each of the HLRs is positioned after the first synchronization between the respective HLRs has been completed; and wherein the first synchronization comprises: an initial synchronization between the HLRs over an Internet Protocol (IP) network with respect to subscriber information of a terminal registered in its own system upon initial setup of the wireless network systems in the multi-zone arrangement, the synchronization being in accordance with a set system ID; synchronization of the subscriber information upon a request to alter or delete the subscriber information from a user through a User Interface (UI) after the initial synchronization has been completed, the synchronization being performed by updating the HLR of the system with the altered or deleted subscriber information and, thereafter, by sending the updated subscriber information to the HLRs of interfaced wireless network systems in respective zones in accordance with the set system ID over the IP network; and synchronization of the subscriber information due to position registration modification upon a position registration message being received from an arbitrary wireless terminal after the initial synchronization process has been completed, the synchronization being performed by updating position registration and subscriber information in its own HLR and, thereafter, by sending the updated subscriber information to each of the interfaced wireless network systems in the multi-zone arrangement over the IP network, upon a determination that the wireless terminal has moved from a service area of the system in which the wireless terminal has been registered to its own service area based on position information of the received message.