COMMUNICATION SYSTEM, RELAY UNIT, OVERWRITE REGISTRATION/DELETION OF ADDRESS CONVERSION INFORMATION, AND METHOD THEREFOR

PROBLEM TO BE SOLVED: To obtain a communication system enabling accurate overwrite registration or deletion of address conversion information on a basis of each application of a communication terminal, and to provide a method of overwrite registration/deletion of the address conversion information. SOLUTION: The communication system is constituted with a relay unit 100A for interconnecting an internal network INW and an external network ENW, and the communication terminal accommodated in the above relay unit. In the relay unit, when an overwrite registration request or a deletion request of the address conversion information comes from an application of the communication terminal, an authentication processor 60 is provided for deciding the authenticity of the above overwrite registration request or the deletion request. In a transmission processor of the communication terminal, on requesting the overwrite registration or the deletion of the address conversion information, there is provided a function of generating the overwrite registration request or the deletion request having identification information for identifying the request source application incorporated therein, so as to transmit to the relay unit. COPYRIGHT: (C)2007,JPO&INPIT