| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To allow a control program to operate only on a specific PLC. <P>SOLUTION: An access request receiving unit 11 inputs a control program and a random number. An authentication processing unit 10b performs hash operation on a random number and a serial ID unique to a PLC 200. An authentication ladder automatic generation unit 13 selects a dedicated device based on a hash number and generates an authentication ladder showing the selected dedicated device. An authentication ladder insertion unit 14 inserts the authentication ladder to the control program to store it. When the control program is executed, the authentication processing unit 10b performs hash operation on the random number and the serial ID, and a dedicated device setting unit 17 selects a dedicated device based on the hash value, and turns ON the selected dedicated device, and a control program execution control unit 16 executes the control program. If the dedicated device corresponding to the authentication ladder is ON, the control program properly operates, and if it is not ON, the control program does not operate. <P>COPYRIGHT: (C)2011,JPO&INPIT</p> |
