Design Optimization of Time-Triggered Ethernet based on Routing and Scheduling Strategy

摘要

The Time- Triggered Ethernet (TTE) provides strictly deterministic and congestion-free for safety-critical realtime applications through precise global clock synchronization. It offers three traffic classes: Time-Triggered (TT) traffic with low jitter and bounded end-to-end latency, Rate-Constrained (RC) traffic with bounded end-to-end latency, and Best-Effort (BE) traffic which have no timing guarantees, since it is based on the IEEE 802.3 Ethernet standard and compliant with the ARINC 664p7 standard. The scheduling of TT traffic makes it free of conflicts on the physical links, but only focus on deriving the static schedule timetable of TT traffic, ignoring RC traffic, may increase the latency of RC traffic, such that RC traffic may be unschedulable. To optimize the TTE network, this paper proposes a joint Routing Strategy and Scheduling Strategy, which takes RC traffic into account, such that both TT and RC traffic can be schedulable, and the worst-case end-to-end delay (WCD) of RC traffic can be reduced to meet the demand of the network.