Keywords:
Application layer, Applications, Bus systems, Buses (data processing), Circuit networks, Communication, Communication network, Control equipment, Control systems, Control technology, Data communication, Data interface, Data link system, Data processing, Data services, Data transfer, Definitions, Digital, Digital data, Digital engineering, Digital signals, EDP, Electronic instruments, Electronic systems, Field bus, Guidance systems, Industrial, Industrial facilities, Information interchange, Information processing, Information technology, Interfaces, Interfaces (data processing), Open systems interconnection, OSI, Process control, Process control engineering, Process control systems, Protocol specification, Protocols, Signals, Specification, Specification (approval), Transmission media, Transmission protocol