Patent ID: 8782418

Claim:
An entertainment device, comprising: a communication arrangement operable to receive media data from a media data source; and a storage arrangement comprising a processor coupled to memory, the storage arrangement being operable to store the received media data; in which: the communication arrangement is operable to receive, from a signature data source, signature data that relates to usage rights of the media data; and the storage arrangement having the processor is operable to limit a duration of access to the media data which was received from the media data source in dependence upon the signature data received from the signature data source; wherein the media data comprises encrypted media data, the signature data comprises encryption key data that relates to the encrypted media data, and the entertainment device comprises a decryptor operable to decrypt the encrypted media data in dependence upon the encryption key data; and wherein the encryption key data is dependent upon time reference data that is used to determine a time period during which the media data is accessible, and upon an expiry date that is used to represent a date after which access to the media data is denied, and is also dependent on identity information including one or more of: hardware identity data; account identity data; a hashed data value of the hardware identity data; and a hashed data value of the account identity data; in which the identity information, the time reference data and the expiry date are configured to be evaluated according to a Boolean expression to determine whether usage rights associated with the entertainment device fulfill the usage rights of the media data, so that when the Boolean expression is satisfied the entertainment device is configured to use the media data.