A communication system is provided for communication within a control system. The communication system has a plurality of simple devices connected to an intra-level communications network, each simple device being adapted to directly exchange data with the other simple devices. The communications system also has at least one intelligent device connected to the intra-level communications network, each intelligent device being adapted to directly exchange data with each simple device on the intra-level communications networks. The communication system can have a plurality of intra-level communications networks. The intra-level communications networks can be directly be connected by an intra-level core connector or by an inter-level core connector through an inter-level network of the intelligent devices.