DATA PROTECTION DEVICE AND PROGRAM

PROBLEM TO BE SOLVED: To reduce possibility of leakage of protection object data without inserting overwrite processing for the protection object data into a processing program and without erasing the protection object data just after use. SOLUTION: In a data protection device, regarding protection object data in a memory, management information including address information, length information and access history information on the protection object data is stored (ST11, ST12, ST16). On the basis of the access history information, presence/absence of access to the protection object data is determined at each certain period (ST15-1-ST15-2). If the access has not been made as a result of the determination, on the basis of address information and length information in the management information including access history information used for the determination, the protection object data corresponding to the management information is erased from the memory (ST15-3). COPYRIGHT: (C)2010,JPO&INPIT