On Tuesdays the USPTO publishes new patents. Both of today's Spotlight Patents address aspects of DRM and information security. Assigned to Intertrust, the first patent concerns techniques that use cryptography to protect secure and insecure computing environments. Assigned to Nokia, the second patent concerns techniques for sharing of content protected by digital rights management.
Computation environments are protected from bogus or rogue load modules, executables, and other data elements through use of digital signatures, seals, and certificates issued by a verifying authority. A verifying authority--which may be a trusted independent third party--tests the load modules and/or other items to verify that their corresponding specifications are accurate and complete, and then digitally signs them based on a tamper resistance work factor classification. Secure computation environments with different tamper resistance work factors use different digital signature authentication techniques (e.g., different signature algorithms and/or signature verification keys), allowing one tamper resistance work factor environment to protect itself against load modules from another tamper resistance work factor environment. The verifying authority can provide an application intended for insecure environments with a credential having multiple elements covering different parts of the application. To verify the application, a trusted element can issue challenges based on different parts of the authenticated credential that the trusted element selects in an unpredictable (e.g., random) way, and deny service (or take other appropriate action) if the responses do not match the authenticated credential.
7,690,042, "Method and device for sharing of content protected by digital rights management," assigned to Nokia (FI).
The present invention provides methods and devices allowing a secure way of sharing DRM-protected content. A content holder may share the content under certain restrictions. These restrictions include range-based, time-based or usage-based limitations. The invention offers a secure sharing method preventing copyright violations and preserving the copyright owners control over the content use, while also offering new marketing possibilities to him.