Virtualizing Programmable Logic Controllers: Toward a Convergent Approach

Modern programmable logic controllers (PLCs) are pervasive components in industrial control systems (ICSs) such as supervisory control and data acquisition, designed to control industrial processes autonomously or as part of a distributed system topology. Its success may be explained by its robustness and reliability, being one of the most enduring legacies on modern ICS, despite having evolved very little over the last years. This letter proposes an x86-based virtual PLC (vPLC) architecture that decouples the logic and control capabilities from the I/O components, while virtualizing the PLC logic within a real-time hypervisor. To demonstrate the feasibility of this concept, the topic of real-time virtualization for x86 platforms is analyzed, together with an evaluation study of the properties of real-time workloads in partitioned hypervisor environments.