On Tuesdays the USPTO publishes new patents. Both of today's Spotlight Patents address aspects of digital rights management. Assigned to Apple, the first patent concerns a token passing technique for media playback devices. Assigned to Microsoft, the second patent concerns techniques for offline playback of advertising supported media.
7,975,312, "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.
7,975,310, "Offline playback of advertising supported media," assigned to Microsoft.
Enforcing rendering of advertisements and other predetermined media content in connection with playback of download selected media content. Playback of selected media content is made conditional on acquisition of a locally cached playback token in response to playback of the predetermined content. The playback token may be implemented as a digital rights management (DRM) license acquired from a local cache in response to playback of the predetermined content. Another aspect involves a downloading ads or other predetermined content with associated playback tokens in a local cache.