| 摘要 |
PROBLEM TO BE SOLVED: To realize the data security of a medium with an easy processing by reading intrinsic ID from the medium to be accessed and terminal ID from a terminal and permitting access to be possible to the medium only when they are correct. SOLUTION: Intrinsic ID is read from the medium to be accessed by a security means 12 and terminal ID at every terminal is read from the terminal concerning the medium 5 where intrinsic ID is previously written and access is made to be possible only when intrinsic ID and terminal ID are correct. At this time, the security means 12 are provided at every terminal or every control program of the terminal and the ciphering and deciphering of medium data are executed by intrinsic ID and terminal ID. Besides, medium data is ciphered or deciphered by intrinsic ID, terminal ID and user ID. Therefore, when medium ID, intrinsic ID and terminal ID of the medium 5 are checked and recognized that they are OK, writing and reading ciphered data are made to be possible. |
