Adopting Microservices for Industrial Control Systems: A Five Step Migration Path

Microservices are widely used by large internet companies as they support scalable systems with high resilience and fault-tolerance, flexible and agile development, and continuous delivery enabling fast time to market. Hence, there is an increasing interest in adopting microservices in the field of industrial automation. This raises the question, if and to what degree this architectural style can also be applied for the development of industrial control systems (ICS). In this paper, we have systematically analyzed the applicability of microservices for ICS development. Together with domain experts from industry, we have developed a migration path from a monolithic ICS towards cloud-ready systems based on microservices. By studying the central principles for microservice development and operation, we found that microservices can be applied in the context of ICS and the use of microservices leads to increased flexibility with regard to frequent software releases and the development of new deployment variants. However, communication between real-time services is still an open research challenge that poses a potential technical risk in the migration towards adopting full microservice-based system architectures.