| 摘要 |
PROBLEM TO BE SOLVED: To provide an encryption apparatus for preventing an illegal copy from a digital recorded recording medium. SOLUTION: In a first encryption means, data are encrypted by a first key, in a second encryption means, the first key is encrypted with a plurality of predetermined second keys, and in a third encryption means, the first key is encrypted by the first key itself. As a result, only a legal person who has at least one of the plurality of second keys can obtain the first key, thereby obtaining plain data of the data encrypted by the first key. Further, illegal action to sell media by the illegal copy is prevented and the copyright can be protected. COPYRIGHT: (C)2004,JPO&NCIPI |
