abstract |
A system for controlling use and distribution of digital works. The present invention allows the owner of a digital work to attach usage rights to their work. The usage rights define how the individual digital work may be used and distributed. Instances of usage rights are defined using a flexible and extensible usage rights grammar. Conceptually, a right in the usage rights grammar is a label associated with a predetermined behavior and conditions to exercising the right. The behavior of a usage right is embodied in a predetermined set of usage transactions steps. The usage transaction steps further check all conditions which must be satisfied before the right may be exercised. These usage transaction steps define a protocol for requesting the exercise of a right and the carrying out of a right. |