Distributed industrial control systems — a critical review regarding openness

Abstract The term “open system” is used in a variety of ways, in many different situations. In particular, almost all vendors of distributed control systems (DCSs) for process automation claim to provide an open system, in information sheets, etc. This paper presents a state-of-the-practice study on open systems, where a large number of commercial DCSs have been examined. The main focus is on achieving interaction between components from different vendors in a distributed DCS environment. Here, the study has clearly shown that the DCSs of today are not very open. The fields in which openness can actually be achieved today have been distinguished and are dealt with in some detail.