| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for easily carrying out PIN lock release on a user's IC card without making a password for lock release identifiable by another person even when a user and a manager are separated from each other, a device used by a manager and a client device. SOLUTION: The PIN lock release method comprises the following procedure. When a client device 2 is PIN-locked, a random number A achieved by making a user identification number U random and a user identification number U of a user are transmitted to a manager at a remote place. The manager inputs the random number A and the number U to a PIN lock release device 3 to check whether a notifier is a proper user or not. After the check, a code B is created by encrypting manager PIN, and this is informed to the user. The user inputs the code B to the client device 2 to achieves the manager PIN for releasing the PIN lock. |
