End System Scheduling Impact in Heterogeneous TSN/TAS Networks
Young Min Kim, Seong Hyeon Lim, Young Soo Do, Sung Bhin Oh, Sung Keun Cha, Hyeok Jun Choi, Beom Gi Suh, Jae Wook Jeon · 2025
This paper experimentally investigates the performance impact of applying different legacy scheduling algorithms, specifically First-In, First-Out (FIFO), Strict Priority Queuing (SPQ), and Stochastic Fairness Queuing (SFQ), on end systems when traffic traverses a central Time-Sensitive Networking (TSN) switch configured with the Time-Aware Shaper (TAS, IEEE 802.1Qbv). We established an experimental setup with legacy PCs and a TSN switch implementing a specific TAS schedule. Prioritized traffic streams were generated, and performance metrics including throughput, packet loss, and latency were measured under each end-system scheduling algorithm. The results demonstrate that the TSN switch’s TAS mechanism and internal scheduling policies largely dominate overall performance, with limited impact from the end-system scheduler choice on throughput and loss. Low-priority traffic consistently suffered from high loss and latency due to scheduling within the switch. However, SFQ scheduling on end systems showed a tendency towards lower average latency compared to FIFO and SPQ. These findings highlight the critical role of TSN switch configuration in heterogeneous networks, while also suggesting that end-system scheduling strategies, particularly fairness-based approaches like SFQ, can still influence latency characteristics. The importance of time synchronization for optimal TAS performance was also observed.