Transparent Fault Tolerance for Real-Time Automation Systems

Developing software is hard. Developing software that is resilient and does not crash at the occurrence of unexpected inputs or events is even harder, especially with IoT devices and real-time requirements, e.g., due to interactions with human beings. Therefore, there is a need for a software architecture that helps software developers to build fault-tolerant software with as little pain and effort as possible. To this end, we have designed a fault tolerance framework for automation systems that lets developers be mostly oblivious to fault tolerance issues. Thus they can focus on the application logic encapsulated in (micro)services. That is, the developer only needs to specify the required fault tolerance level by description, not implementation. The fault tolerance aspects are transparent to the developer, as the framework takes care of them. This approach is particularly suited for the development for mixed-criticality systems, where different parts have very different and demanding functional and non-functional requirements. For such systems highly specialized developers are needed and removing the burden of fault tolerance results in faster time to market and safer and more dependable systems.