Information recording medium, information processing device, information processing method, and computer program

A method for using encrypted content stored on an information recording medium, the method comprising:

• reading an encrypted content file comprising encrypted content, usage right information corresponding to the encrypted content, and encryption key information necessary for decrypting the encrypted content from the information recording medium, wherein the information recording medium is disc-shaped, wherein the usage right information comprises a limitation on period of use of the encrypted content;
• determining whether use of the encrypted content is permitted based on the usage right information;
• and
• using the encrypted content when the determination is positive;
• wherein the information recording medium comprises an inner circumferential part storing non-encrypted content and an outer circumferential part storing the encrypted content, and
• wherein the non-encrypted content is copy protected.

A storage medium for storing a computer readable program for performing a process, when executed by a processor, for using encrypted content stored on an information recording medium, comprising:

• reading an encrypted content file comprising encrypted content, usage right information corresponding to the encrypted content, and encryption key information necessary for decrypting the encrypted content stored in the information recording medium, wherein the usage right information comprises a limitation on period of use of the encrypted content;
• determining whether use of the encrypted content is permitted based on the usage right information;
• and
• using the encrypted content when the determination is positive;
• wherein the information recording medium comprises an inner circumferential part storing non-encrypted content and an outer circumferential part storing the encrypted content, and
• wherein the non-encrypted content is copy protected.