Patent ID: 7937327

Claim:
An apparatus for reproducing a music content composed of at least one content material in accordance with security information of the music content, the apparatus comprising: a processor; a reading section that accesses a recording medium which records a data file of the music content having a chunk structure including an encrypted content material chunk, an encrypted security information chunk, and an encryption information chunk, the content material chunk comprising substantial data of the content material and first identification information for uniquely identifying the content material, the security information chunk comprising security information of the content material and second identification information for uniquely identifying the content material, the encryption information chunk comprising a first encryption key for decrypting the content material chunk and a second encryption key for decrypting the security information chunk, the reading section that reads the first identification information from the content material chunk and the second identification information from the security information chunk; a comparison section that compares the first identification information read from the content material chunk with the second identification information read from the security information chunk; and a reproducing section that permits reproduction of the content material when the comparison section determines that the first identification information read from the content material chunk matches the second identification information read from the security information chunk, and that does not permit the reproduction of the content material when the comparison section determines that the first identification information does not match the second identification information, wherein the reading section decrypts the content material chunk using the first encryption key and decrypts the security information chunk using the second encryption key to read the respective first and second identification information from the recording medium.