| 摘要 |
PURPOSE:To easily detect a working by the forged program of a terminal equipment in a central processing unit by comparing the result of the testing arithmetic operation by a testing arithmetic means and the result of the testing arithmetic operation by the testing arithmetic means of the central processing unit. CONSTITUTION:Based on a parameter (code initial value 20 and code key 21) generated by a central processing unit 2, a terminal equipment 1 and the central processing unit 2 execute the completely same testing arithmetic operation and the central processing unit 2 compares and collates the result. Thus, the central processing unit 2 can detect the cases when the program of the terminal equipment 1 is not a fair program expected by the central processing unit 2, namely, when the program of the terminal equipment 1 is falsified, and when the working is executed by an unfair program, and communication with the terminal equipment 1 can be prohibited. Since a parameter is generated by a random number generating part 12 completely at random, the testing arithmetic operation result is also different every time, and further, since a DES code is used as a testing arithmetic operation, the reliability of the testing arithmetic operation result is high. |
