TYPE SYSTEM FOR ACCESS CONTROL LISTS

A method and storage media for performing access resolution using ACL types is provided. Under an AND semantic, an intersection set formed from the types of multiple ACLs protecting a resource may be utilized to efficiently determine whether a request for a privilege to access the resource is granted or denied. If the privilege is not a member of the intersection set, the privilege cannot be granted. A union set may be used for an OR semantic. A global ACL type may represent all privileges system-wide or application-wide. A global ACL may represent a system-wide or application-wide access policy. A conjunction of a global ACL and a regular ACL may be stored in a cache. The union set, intersection set, or access resolution may also be cached for subsequent request processing.