Optimizing Message Routing and Scheduling in Automotive Mixed-Criticality Time-Triggered Networks

Upcoming high-bandwidth protocols like Ethernet TSN feature mechanisms for redundant and deterministic (scheduled) message delivery to integrate safety- and real-time--critical applications and, thus, realize mixed-criticality systems. In existing design approaches, the message routing and system scheduling are generated in two entirely separated design steps, ignoring and/or not exploiting the distinct interrelations between routing and scheduling decisions. In this paper, we first introduce an exact approach to generate an implementation with a valid routing and a valid schedule in a single step by solving a 0-1 ILP. Second, we show that the 0-1 ILP formulation can be utilized in a design space exploration to optimize the routing and schedule with respect to, e.g., interference imposed on non-scheduled traffic or the number of configured port slots. We demonstrate the optimization potential of the proposed approach using a mixed-criticality system from the automotive domain.