The Simplex Reference Model: Limiting Fault-Propagation Due to Unreliable Components in Cyber-Physical System Architectures

Cyber-physical systems are networked, component-based, real-time systems that control and monitor the physical world. We need software architectures that limit fault-propagation across unreliable components. This paper introduces our simplex reference model which is distinguished by: a plant being controlled in an external context, a machine performing the control, a domain model that estimates the plant state, and the safety requirements that must be met. The simplex reference model assists with constructing CPS architectures which limit fault-propagation. We present a representative case study to highlight the ideas behind the model and our particular decomposition.