An apparatus generates first shared information that is shared by the apparatus and a recording medium by performing a first bilateral authentication. The apparatus encrypts overwrite data that is used to erase key information item recorded in the recording medium using the first shared information....http://www.google.fr/patents/US7181008?utm_source=gb-gplus-shareBrevet US7181008 - Contents management method, content management apparatus, and recording medium
Contents management method, content management apparatus, and recording medium
