Timing Analysis of AVB Traffic in TSN Networks Using Network Calculus

Abstract

Time-Sensitive Networking (TSN) is a collection of standards that extend Ethernet to support safety-critical and real-time applications. TSN integrates multiple traffic types, i.e., Time-Triggered (TT) traffic scheduled based on Gate-Control-Lists (GCLs), Audio-Video-Bridging (AVB) traffic that requires bounded latencies, and Best-Effort (BE) traffic, for which no guarantees are provided. This paper proposes a Network Calculus-based approach to determine the worst-case end-to-end delays of AVB traffic in a TSN network with both non-preemption and preemption modes. We consider the effects of TT traffic due to GCLs, "guard bands", i.e., time windows that block other traffic from transmitting, and preemption overhead on the service for AVB traffic. We provide a proof of non-overflow condition for AVB credit, which is used to control the AVB traffic transmission. The analysis method is evaluated on realistic test cases, and compared to related work.