Access control for digital content

摘要

A recording arrangement operable to apply access control processing to input data content using a set of one or more content keys and to record access-controlled data content on a content storage medium, the arrangement comprising:
an encryption apparatus having means for encrypting portions of the data content in dependence upon the set of content keys; and an interface to provide a secure data connection between the encryption apparatus and an access control memory device;
an access-control memory device connected to the encryption apparatus via the interface and operable to store securely information from which the private key is derivable;
the encryption apparatus and the access-control memory device co-operating to provide means for generating content access control data comprising at least one encrypted version of a respective subset of the set of content keys, the content access control data being generated in dependence upon at least one public key of a respective public key / private key pair associated with a further access-control memory device so that decryption of the set of content keys requires access to a private key of the respective public key / private key pair, the at least one public key used in the generation of the content access control data depending on data stored by the access-control memory device; and
the recording arrangement having means for recording the encrypted information content and the content access control data on the content storage medium such that the information content may selectively be decrypted in dependence upon access to the private key of the respective public key / private key pair.