Reliable Routing and Scheduling in Time-Sensitive Networks

Abstract

Time-Sensitive Networking (TSN) standards were proposed to deliver real-time data with deterministic delay. TSN realizes the deterministic delivery of time-sensitive traffic by establishing virtual channels with specific cycle intervals. However, existing work does not consider the reliable delivery of time-sensitive traffic. In addition, existing work generally considers scheduling in the ideal environment, and cannot handle random events such as network jitter and packet loss. In the paper, we introduce path redundancy and seamless redundancy as the basis of reliability, and propose reliable routing and scheduling problems with objectives to achieve good network throughput and link load balancing. We propose a routing heuristic and a scheduling heuristic to generate redundant transmission paths and schedules for time-sensitive traffic, respectively. Further, we propose a joint optimization algorithm to optimize the feasible solutions produced by routing and scheduling. In particular, we improve the scheduling mechanism of TSN, so that the our scheduling algorithm can adapt to the random and dynamic events in real network. Evaluations were carried out in several test cases with a self-developed TSN testbed. The results show our approaches can efficiently achieve good network throughput and link load balancing while ensuring time-space reliability.