UNAUTHORIZED DEVICE DETECTION DEVICE AND UNAUTHORIZED DEVICE DETECTION SYSTEM

摘要

There is provided an unauthorized device detection system capable of finding and identifying a device which has been manufactured or altered in an unauthorized way. A DVD player (400a) writes in its device ID into a memory card (200a). When a user purchases a content, a register device (300) reads out a medium ID and a device ID from the memory card (200a) and transmits the medium ID and the device ID to a management server device (100). The management server device (100) calculates the total number of the medium ID corresponding to the received device ID from the sets of the medium ID and the device ID stored in advance and the set of the medium ID and the device ID received, and compares the calculated total number to a threshold value. If the number exceeds the threshold value, it is estimated that the DVD player identified by the received device ID is an unauthorized device.