 Ontology Systems develop a real-time network and service topology platform and toolset used for service and customer assurance applications.They are also used as a source of data for active inventory systems to support visualization, troubleshooting, workflow and data alignment for NOC, SOC, and Care systems.Using a graph-data based approach and a graph pattern matching inference/rules engine, they discover or compute most of the relationships between data stored in the CSPs NMS/EMS, billing, assurance, fulfilment, and CRM systems to construct a mapping of tags, pointers, and relationships to accurately represent a service and its underlying virtual, logical and physical resources.