Patent ID: 7380139

Claim:
A digital data recording apparatus for recording digital data on a recording medium, the digital data recorded on the recording medium being reproducible by a playback apparatus, said digital data recording apparatus comprising: a communication unit to receive encrypted digital data via a digital network; a decryption unit to decrypt the encrypted digital data received by said communication unit; an encryption unit including a plurality of encryption sub-units each encryption sub-unit being to re-encrypt decrypted digital data using a corresponding one of a plurality of encryption methods having different security levels, wherein said encryption unit includes a first encryption sub-unit to re-encrypt the decrypted digital data by using an encryption key that has been created according to identification information of the recording medium, and a second encryption sub-unit to re-encrypt the decrypted digital data by using an encryption key that has been created according to identification information of the playback apparatus; a recording unit to record digital data that has been re-encrypted by said encryption unit on the recording medium; and a controller to control said decryption unit and said encryption unit, and to (i) obtain information relating to the recording medium, (ii) select one of said plurality of encryption sub-units based on the obtained information, and (iii) control said selected encryption sub-unit to re-encrypt the digital data that has been decrypted by said decryption unit, wherein said controller is to determine whether the recording medium is removable from the playback apparatus, control said first encryption sub-unit to re-encrypt the decrypted digital data when the recording medium is removable from the playback apparatus, and control said second encryption sub-unit to re-encrypt the decrypted digital data when the recording medium is not removable from the playback apparatus.