| 摘要 |
<p>The present invention is a PLC monitoring system (10) which monitors the operational state of a plurality of PLCs (1) which control an object to be controlled (5) in order to monitor the operational state of the PLCs (1), wherein the system is characterized in that a PLC (1b), from a PLC (1a) other than itself, acquires a control command which has been output from a user program which is being executed at the PLC (1a), and on the basis of the acquired control command, generates verification-use data. Then, the PLC (1b), using the verification-use data, verifies whether or not the transmission source PLC (1a) for the control command has been infected by a virus, or transmits the verification-use data to a PC (2) so that, by way of the PC (2) displaying the verification-use data upon a display device, the user performs verification of the infection of the PLC (1a) with the virus.</p> |
