When information to be recorded is encrypted by using an encryption key, an encryption key based on inherent information inherent in a recording medium is generated. The information to be recorded on the recording medium is encrypted based on the encryption key. The inherent information inherent in the...http://www.google.es/patents/US5917910?utm_source=gb-gplus-sharePatente US5917910 - Encrypting method and apparatus, recording method, decrypting method and apparatus, and recording medium
Encrypting method and apparatus, recording method, decrypting method and ...
