| 摘要 |
PROBLEM TO BE SOLVED: To impose secure protection. SOLUTION: A ciphering key generation part 4 generates a ciphering key on the basis of information characteristic of a recording medium supplied from a characteristic information generation part 5, a ciphering part 3 ciphers information to be recorded on the recording medium with the ciphering key to make a master disk 12, and a disk 15 is made finally. A reproduction part 16 reproduces the disk 15, a deciphering key generation part 18 generates a deciphering key from the reproduced data, and a deciphering part 17 deciphers the ciphered data reproduced by the reproduction part 16 according to the deciphering key. |
