Extensible rights expression processing system

A method for processing one or more rights expressions including a request that requests a usage right associated with a resource for a principal, and a grant that issues a usage right associated with a resource to a principal, said method comprising the steps of:

• registering plug-in components with a framework;
• making a programmatic call to said framework to authorize requests for usage rights set forth in said one or more rights expressions;
• finding one or more appropriate plug-in components configured to evaluate each of said requests set forth in said one or more rights expressions;
• invoking said appropriate plug-in components;
• evaluating said request against said grant;
• and
• returning an authorization result that indicates whether said request is authorized by said grant.

An extensible grammar-based rights expression system for processing one or more rights expressions, said system comprising:

• a framework having an extensible architecture with one or more extensibility points for adding extensions to said grammar;
• and
• an interpreter adapted to evaluate said one or more rights expressions;
• wherein said extensions define semantics and syntax of new rights expressions to allow processing of said new rights expressions.

A method for processing one or more rights expressions including a request that requests a usage right associated with a resource for a principal, and a grant that issues a usage right associated with a resource to a principal, said method comprising the steps of:

• providing an extensible grammar-based rights expression system having an extensible architecture with an interpreter adapted to evaluate said one or more rights expressions;
• evaluating said request against said grant using said interpreter;
• and
• returning an authorization result that indicates whether said request is authorized by said grant.