| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an information access management method and apparatus capable of reducing the danger of losing an encryption key (Kt or Title Key) even on the occurrence of a power failure on the way of processing with respect to encryption key production. <P>SOLUTION: When a backup file (MKB. BUP) of the Read Write MKB exists at start of power application after the power is interrupted due to, e.g. the power failure, either the Read Write MKB (MKB. NEW) or its backup file (MKB. BUP) is used (ST 426 or ST 428) depending on the status of generations of three key files TKF1, TKF2, TKF3, and two of the three key files (TKF1, TKF2, TKF3) are used to decrypt the encryption key (Kt or Title Key) (ST 430). <P>COPYRIGHT: (C)2008,JPO&INPIT</p> |
