UNAUTHORIZED CONNECTION DETECTION SYSTEM AND UNAUTHORIZED CONNECTION DETECTION METHOD

摘要

[PROBLEMS] To provide an unauthorized connection detection system for detecting an unauthorized connection to a network by spoofing in which an unauthorized terminal device having no connection authority rewrites the IP address and the MAC address, and performing a countermeasure. [MEANS FOR SOLVING PROBLEMS] A monitoring-dedicated program is contained in a terminal device having the connection authority to a network and executes a report upon start of connection to the network and a constant report during connection to the network. A terminal device connected in an unauthorized way by spoofing does not have the monitoring program. Accordingly, even when connection to the network is allowed by matching of the IP address or the like, the connection start report and the constant report cannot be received. Thus, the communication of the terminal device is interrupted.