| 摘要 |
PROBLEM TO BE SOLVED: To improve the safety and reliability by variable setting a password code and letting specific persons know it, and collating an inputted password code with the set password code and identifying the person. SOLUTION: On a center device 2, a unique telephone number is determined and a radio telephone line between connecting facilities 3 and an external portable telephone set 10 is connected and disconnected on the basis of the telephone number. Then a random number generator 2b generates a random number, which is used to set the password code. The set password code is updated and stored in a password code memory 2c. Further, the telephone number of the telephone set 10 is collated with permission data (registered telephone number) in the memory 2c in response to the origination by the portable telephone set 10 and when they match each other, it is decided the caller is a specific person to send the password code, but when not, it is decided that the caller is not a specific person to inform the telephone set 10 of rejection. Consequently, a leak of the password number and, for example, illegal passage by a retired person can be prevented. |
