RECORDING DEVICE AND METHOD, DECODING DEVICE AND METHOD, PROVIDED MEDIUM, AND INFORMATION RECORDING MEDIUM

摘要

Encrypted information is made available to devices other than one to which the information is originally supplied, while an illegal use being prevented. A mutual authentication unit (17) and an IC card (4) mutually authenticate each other. An encryption unit (15), being a mobile key, encrypts a contents key. A recording unit (12) records encrypted contents and the contents key encrypted by the encryption unit (15) onto an optical disk (5).