INFORMATION PROTECTION METHOD FOR INFORMATION STORAGE MEDIUM, AND INFORMATION STORAGE MEDIUM RECORDING/REPRODUCING DEVICE

摘要

PROBLEM TO BE SOLVED: To provide an information protection method for an information storage medium capable of protecting the information of the information storage medium without providing a control information area for the information protection of the information storage medium different from information data in the information storage medium. SOLUTION: When a requirement packet to the external storage medium 1 is a writing requirement packet to a root directory to the external storage medium 1, a medium identification number preservation area 10 is searched by identifier data of the writing requirement packet to acquire a medium identification number of the external storage medium 1, data of a root directory area of the external storage medium 1 are identified by the acquired medium identification number and stored in a preservation storage medium 11 different from the external storage medium 1 as a root directory data file, and root directory data of the writing requirement packet are stored in the file. COPYRIGHT: (C)2005,JPO&NCIPI