| 摘要 |
<P>PROBLEM TO BE SOLVED: To permit a content provider to inexpensively provide a recording medium and to permit a user to purchase an inexpensive recording medium, even when many contents are recorded on one recording medium. <P>SOLUTION: An optical disk 1 is provided with a reproduction permission information recording area 1e. In a contents recording area 1c, the many contents such as videos and music are recorded by the contents provider in the state in which the reproduction of all of the contents or a part of the plurality of contents is restricted, for example, the contents data are encrypted. When reproducing the contents in which the reproduction is restricted, the user acquires the reproduction permission information, for example a decryption key, from the content provider. The acquired reproduction permission information is recorded in the reproduction permission information recording area 1e of the optical disk 1 by a content reproduction device. The content reproduction device reproduces the contents when the reproduction permission information is recorded in the reproduction permission information recording area 1e for the contents instructed so as to be reproduced. <P>COPYRIGHT: (C)2006,JPO&NCIPI |
