Reviewing cached user-group information in connection with issuing a digital rights management (DRM) license for content

摘要

A computer network has storage devices organized into X levels and storing element-group information. To determine whether an element is a member of any target groups, each target group is validated by searching the storage devices to find a target group item and, if found, placing the target group in a validated target bin (V). Also, , the element is validated by searching the storage devices to find an element item, and if found, determining from the item all groups that the element is listed as being a member of and placing such member-of groups in a search bin (S). If (S) intersects (V), the element is a member of a target group. If not, all groups in (S) are moved to a queue (Q1) corresponding to the storage device at level 1 and an iterative process searches for a membership path from the element to any target group.