Supporting vPLC Networking over TSN with Kubernetes in Industry 4.0

The shift in the industrial ecosystem from closed and specialized technologies to the open and general-purpose vision of Industry 4.0 faces numerous challenges. The absence of viable solutions to replace Programmable Logic Controllers (PLCs), vital components in control infrastructures, with their virtual equivalent (vPLCs) embodies those difficulties. In this paper, we introduce a framework that aims at truly materializing the integration between Operational (OT) and Information Technologies (IT) by defining an open, general ecosystem around vPLCs. Previous work either could not meet the performance and determinism requirements of the OT or did so by sacrificing the generality of IT. Building on these experiences, our framework provides both flexibility and efficiency by clearly separating the data path for OT and IT communications. To do that, we integrate tools from both domains: techniques to ensure low network performance and variability (TSN), to ease portability (OPC-UA), and to enhance management and deployment (Kubernetes). Experiments on a real testbed show that vPLCs within our framework can meet strict performance requirements and yet provide the same flexibility as cloud-based applications.