Patent ID: 7024393

Claim:
A digital rights management (DRM) system operating on a computing device when a user requests that a protected piece of digital content be rendered by the computer device in a particular manner, the system comprising: a rendering application by which the requested digital content is rendered; a license store for storing one or more digital licenses on the computing device, the license store providing access to the one or more digital licenses separately from the requested digital content; a license evaluator for determining whether any licenses stored in the license store correspond to the requested digital content, for determining whether any such corresponding licenses are valid, for reviewing license rules in each such valid license, and for determining based on such reviewed license rules whether such license enables the requesting user to render the requested digital content in the manner sought; a state store for maintaining state information corresponding to each license in the license store, the state information being created and updated by the license evaluator as necessary; and a black box for performing encryption and decryption functions as part of the evaluation of any license, wherein the license evaluator selects an enabling, valid license and works with the black box to obtain a decryption key (KD) from the selected license, and wherein the black box employs such decryption key (KD) to decrypt the protected digital content, and wherein the black box decrypts the protected digital content when the license evaluator determines that a license in fact enables the requesting user to render the requested digital content in the manner sought.