Patent ID: 8266250

Claim:
A communication detection device comprising: a log dividing unit to read a communication log from a communication log storage unit that stores the communication log that records information concerning communication data exchanged between devices linked to a network, and divide the communication log into parts corresponding to individual object devices based on a sender and a destination of the communication data recorded in the communication log; a divided log analysis unit to analyze the parts of the divided communication log extract the communication data in which a connection request to each device has been issued, generate a response success/failure table in accordance with whether a response from the device that is an object of the connection request has been detected, and store the response success/failure table in a response success/failure table storage unit; and a determination unit to determine, based on the response success/failure table stored in the response success/failure table storage unit, when a time period wherein no response is obtained from the device satisfies a criterion condition determined in advance, that peer-to-peer communication has been performed.