| 摘要 |
<P>PROBLEM TO BE SOLVED: To improve security in an HDD. Ž<P>SOLUTION: Magnetic recording information (Ia) including ROM information (Ib) recorded in a magnetic disk 10 by physical arrangement of recording bits, and content information (Io) and authentication information (Ik) recorded by magnetizing the recording bits is read by a head 19 and DC-erased using the head 19 after reading. Further, after DC erase, the ROM information is read, and the content information is acquired from the information (Ia), (Ib) and (Ik) by an operating section 90. In this way, as the content information is acquired using the ROM information which can be read only after the DC erase, the content information does not remain on the magnetic disk when the content information is acquired. Therefore, the content information is prevented from being acquired (illegally copied) by a third party after the content information is read. Ž<P>COPYRIGHT: (C)2010,JPO&INPIT Ž
|
