Tuesdays the USPTO issues new patents. Three InterTrust DRM-related patents issued today, and rather than choosing two of them, today's Spotlight Patents note all three. The first concerns techniques for software self-checking. The second concerns techniques for using cryptography to protect secure computing environments. The third concerns techniques for managing the distribution of electronic content.
Software self-checking mechanisms are described for improving software tamper resistance and/or reliability. Redundant tests are performed to detect modifications to a program while it is running. Modifications are recorded or reported. Embodiments of the software self-checking mechanisms can be implemented such that they are relatively stealthy and robust, and so that it they are compatible with copy-specific static watermarking and other tamper-resistance techniques.
7,581,092, "Systems and methods using cryptography to protect secure computing environments," assigned to InterTrust.
Secure 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 or other executables to verify that their corresponding specifications are accurate and complete, and then digitally signs the load module or other executable based on tamper resistance work factor classification. Secure computation environments with different tamper resistance work factors use different verification 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, different tamper resistance work factor environment. Several dissimilar digital signature algorithms may be used to reduce vulnerability from algorithm compromise, and subsets of multiple digital signatures may be used to reduce the scope of any specific compromise.
7,580,988, "System and methods for managing the distribution of electronic content," assigned to InterTrust.
The present invention provides systems and methods for transfering electronic information from one location to another such that only one original work exists at a given time. The methods and systems of the present invention allow distribution of originals without requiring a registration authority or other entity to vouch for what constitutes an "original" piece of information, thus reducing (or eliminating entirely) the need to centrally record changes in ownership each time originals change hands.