enterprise identity management systems control access to information derived from identity - related data stored in various data repositories . an identity - based management system can automatically and dynamically compute derived data when the source data changes . rule - base tools can be used to compute derived data from arbitrary attribute - based datasets . dynamic computation of identity - based attributes within information system servers allows data to be aggregated and normalized from multiple data sources deployed across an organization so that updated related information can be persisted and pushed to various servers in the organization .