Using FTT-ethernet for the coordinated dispatching of tasks and messages for node replication

The Flexible Time Triggered (FTT) paradigm provides online flexible scheduling for distributed embedded systems but it does not present adequate fault tolerance mechanisms so as to reach a very high reliability. Adding the adequate fault tolerance mechanisms to FTT-based architectures would open room for adaptive yet highly dependable systems. In this work we present a fault-tolerant system architecture for control applications that adds a node replication scheme with voting on top of an FTT-based system. Using a previously proposed network-centric approach we show how to coordinate the execution of the different phases for a typical control application in our system architecture, i.e. we show how to trigger the execution of tasks in node replicas and the transmission of messages in the communication channel, using the underlying FTT protocol. At the end, we demonstrate how to apply this idea of coordinated dispatching to one concrete control application, ball-on-plate.