An electronic control unit (ECU) controls one or more electrical systems or subsystems in a vehicle. A modern motor vehicle might contain 80 or more ECUs. An ECU transmits and receives frames (also called messages) on a closed Controller Area Network (CAN) bus.
The NI-XNET Database Editor displays ECUs only as transmitters and receivers of frames within clusters. The same ECU might appear as part of different clusters in the database; however, in an exported FIBEX file, the ECU appears as different entities.