Role Logic and its Application to the Analysis of Process Control Systems from the Socio–Technical System Perspective

Security requirements for process control systems can be viewed as a social construct derived from the culture and society within which the requirement is said to exist. To capture and understand these requirements we need to make use of a formal reasoning system that supports a rigorous deductive process. Socio---Technical Systems thinking offers us the ability to express the wider socio---context within which an ICT system can be said to operate. In this paper we will extend the π-calculus model of actions via the creation of role logic. Then via the application of responsibility modelling and role logic we will demonstrate how a model of a Socio---Technical process control system can be created and analysed so as to identify critical dependancies.