| 摘要 |
PROBLEM TO BE SOLVED: To realize improvement in security of a portable communication system by detecting existence of a clone terminal at an early stage to suppress regular user's damage to the minimum. SOLUTION: The clone terminal detection system holds status information in a portable communication terminal 20 and an exchange 50, respectively, and includes an updating means of the terminal status information to update the status information held in the portable communication terminal on the basis of communication time, an updating means of the exchange status information to update the status information held in the exchange on the basis of the communication time, and an authentication means to judge whether or not the communication is permitted on the basis of the status information held in the portable communication terminal and the status information held in the exchange. |
