Thursdays the USPTO publishes new patent applications. Both of today's Spotlight Applications concern various aspects of DRM. Assigned to Apple, the first application discloses a token passing technique for media playback devices. Assigned to Microsoft, the second application discloses a content encryption schema for integrating digital rights management with encrypted multicast.
20080168568, "Token passing technique for media playback devices," assigned to Apple.
A digital rights management (DRM) system for distribution of digital content such as audio or video uses a token passing scheme to enhance security of the content from unauthorized access and use, including access by unauthorized players. The token is requested from the central content or DRM server by a host device such as a user's computer, using security related information. The token is then passed to a media player associated with the host device, the token being encrypted using a key special to that particular player. Upon receipt of the token, the player transmits back to the server certain related security information confirming receipt of the token and in return receives keys for decryption of the associated digital content. In the absence of proper passing of the token, player access to the content, or further access to other content, is denied. This also allows the player to communicate directly with the server for obtaining the keys.
20080165956, "Content Encryption Schema For Integrating Digital Rights Management With Encrypted Multicast," assigned to Microsoft.
Systems and methods provide a content encryption schema for integrating digital rights management (DRM) in a multicast/broadcast encryption system. In one implementation, an exemplary integrated key schema provides content encryption keys that can be employed by a multicast or broadcast process, while providing DRM protection of recorded multicast content via a single DRM decryption secret. The integrated key schema provides high security and allows encrypted multicast content to be saved directly to local files. A license server can efficiently manage and generate DRM keys to be delivered to clients because only a single key needs to be delivered per license to a client. The integrated key schema can be applied together with conventional broadcast or multicast encryption techniques.