Enhancing Schedulability and Throughput of Time-Triggered Traffic in IEEE 802.1Qbv Time-Sensitive Networks

Thanks to the standards being developed by IEEE Time-Sensitive Networking (TSN) Task Group, the classical IEEE 802.1 Ethernet architecture is now enhanced to accommodate real-time and safety-critical requirements emerging in various cyber-physical systems. The deterministic nature of the communication is achieved through the time-triggered traffic, which requires introducing strict scheduling constraints that may be an obstacle in finding a feasible schedule. In this article, we propose a simple hardware enhancement of a switch along with a relaxed scheduling constraint that increases schedulability and throughput of the time-triggered traffic but maintains the deterministic nature and timeliness guarantees in a TSN network. We give a formal proof to justify the claims and an algorithm benchmarking and experimental validation to demonstrate the gains. The results show that the number of flows that can be scheduled in the model with the relaxed constraint is on average by 75.1 % larger than in the traditional model.