Patent ID: 7937084

Claim:
A communication network system comprising: a plurality of heterogeneous wireless communication systems; a mobile terminal that communicates with the wireless communication systems; and a location registering device that registers a location of the mobile terminal, wherein the mobile terminal includes an identification-information extracting unit that extracts first identification information specific to a location registration area of each of the wireless communication systems from information received from each of the wireless communication systems, a first storage unit that stores therein correspondence information concerning a correspondence relationship between the first identification information and second identification information of a location registration area managed by the communication network system, and a location-registration requesting unit that extracts the second identification information corresponding to the first identification information based on the first identification information extracted by the identification-information extracting unit and the correspondence information stored in the first storage unit, and transmits location-registration request information for requesting the location registering device to perform a new location registration when the second identification information is updated by a movement of the mobile terminal.