| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To solve a problem wherein a complete check is not implemented because it is checked dependently upon an external device whether a user is authorized to change a program and data, and a system in which a connection to a communication bus is switched by a hardware switch, is a troublesome operation. <P>SOLUTION: The user transmits a security state change report together with a password when changing the program and data. A process controller collates the password and changed a present security state in the case of coincidence. Then the user transmits a change request, and the process controller refers to the present security state to check whether the received change request is permitted, and change is executed when it is permitted. The process controller itself manages and controls the security. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
