The invention relates to a method for decrypting encrypted data stored on
a record carrier, to a corresponding method for encrypting data and to
corresponding apparatuses. In order to provide a high level of protection
for data stored on a record carrier and to prevent that data stored on
different record carriers can be decrypted after a decryption algorithm
has become known the method for decrypting encrypted data according to
the invention comprises the following steps: a) generating a decryption
key (DK) using a unique carrier identifier (UDI) associated with said
record carrier, a hidden key (HK) stored in a hidden channel on said
record carrier and a password key (PK), and b) decrypting said encrypted
data stored on said record carrier using said generated decryption key
(DK).