Network management

A network manager system comprises one or more network controllers in a communications network. The network management system comprises an application level 600 which represents the functionality of a plurality of different composites being hardware and/or software components of different proprietary manufacture and different function capability, and an implementation level 601 which implements control of the composites. The application level is sub-divided into a plurality of application level elements each of which correspond to a function capability of a composite or system, a system being a highest level of composite. The implementation level is sub-divided into a plurality of implementation level elements each of which represents a system, a composite or a component. The internal structure of the elements within the application controller and implementation level corresponds to internal architectures of the systems and composites. As a communications network is assembled from a plurality of different components and composites 604, the network management system can also be assembled using predetermined constructions of composite controllers and component controllers which correspond to specific composites or specific components within those composites.