| 摘要 |
PROBLEM TO BE SOLVED: To make mainly copying protection information, etc., hardly stolen. SOLUTION: A hard disk A has a disk 10 which is previously written in the form of surface shapes, such as slits and ruggedness, with the copying protection information in a prerecording region 13 exclusive of a data memory region 12 on a substrate 11, a pickup section 20 which reads the copying protection information on the disk 10, a copying protection section 42 which performs authentication processing by referencing the copying protection information read by the pickup section 20 in copying the encrypted deter on the data memory region of the disk 10 according to the request of an external apparatus C and outputs the information relating to a cipher key included in the copying protection information toward the external apparatus C admitted to be corrected through this authentification processing and others. |
