| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a portable memory capable of providing sufficient protection functions to data such as a file. <P>SOLUTION: In a memory unit 6, since an encryption key is changed whenever the file (data) stored in a flash memory 35 is used in a microcomputer 43, security is raised. In addition, since the microcomputer 43 periodically performs consistency check of the encryption key, information leakage by unauthorized analysis is prevented. <P>COPYRIGHT: (C)2008,JPO&INPIT |
