| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a multilayered optical disk, an optical disk device, a content reproduction system, and a content reproduction method, which achieve both the protection of the copyright of a content and user friendliness. <P>SOLUTION: Content data are recorded on the ROM layer 22 of the optical disk 2, and essential data showing a file system for managing the content data are recorded on an RE layer 21. A CPU 10 reads the content data using the essential data. Thereafter, the content is reproduced on the basis of the read content data. Next, the number of times of using the content data recorded on the RE layer 21 is incremented by the CPU 10. When the number of times of using after the increment is not smaller than the predetermined upper limit thereof, the essential data recorded on the RE layer 21 are deleted. As a result of this, it becomes impossible to read the content data. However, writing the previously backed-up essential data back onto the RE layer 21 makes it possible to read again. <P>COPYRIGHT: (C)2011,JPO&INPIT |
