Fieldbus is a digital serial, multidrop, data bus for communicationwith low-level industrial control and instrumentation devices suchas transducers, actuators and local controllers. The Physical Layerprovides for transparent transmission of Data Link Layer entitiesacross physical connections. Specifies the requirements forFieldbus component parts. Also specifies the media and networkconfiguration requirements necessary to ensure agreed levels of:a) data integrity before Data Link error checking;b) interoperability between devices at the Physical Layer.