A Survey and Experimental Study of Real-Time Scheduling Methods for 802.1Qbv TSN Networks

Time-sensitive networking (TSN) has been recognized as one of the key enabling technologies for Industry 4.0 and has been deployed in many mission- and safety-critical applications e.g., industry automation, automotive and aerospace systems. Given the stringent real-time requirements of these applications, the Time-Aware Shaper (TAS) draws special attention among TSN’s many traffic shapers due to its ability to achieve deterministic timing guarantees. Many scheduling methods for TAS shapers have been recently developed that claim to improve system schedulability. However, these scheduling methods have not yet been thoroughly evaluated, especially through experimental comparisons, to provide a systematical understanding of their performance using different evaluation metrics in diverse application scenarios. In this article, we fill this gap by presenting a systematic review and experimental study on existing TAS-based scheduling methods for TSN. We first review and categorize the system models employed in these works along with the specific problems they aim to solve, and outline the fundamental and additional considerations in the designs of TAS-based scheduling methods. We then perform an extensive evaluation on 17 representative solutions using both high-fidelity simulations and a real-life 16-node TSN testbed, and comparing their performance in terms of schedulability, scalability, and schedule quality. Through these experimental studies, we identify the limitations of individual scheduling methods and highlight important findings. We also summarize the open issues and future research directions in this area. We expect this work will provide foundational knowledge and performance benchmarks for future studies on real-time TSN scheduling and beyond.