Routing Optimization of Time-Triggered Ethernet Based on Genetic Algorithm

The development of avionics systems has promoted the introduction of the time-triggered concept. The Time-triggered Ethernet (TTE) is a deterministic, synchronous, conflict-free network protocol based on the IEEE 802.3 Ethernet standards and is compatible with ARINC 664p7 protocol. It supports real-time application of mixed-criticality by providing three types of traffic: time-triggered (TT) traffic, which has low jitter and bounded end-to-end delay; rate-constrained (RC) traffic, which has bounded end-to-end delay; and best-effort (BE) traffic, which cannot ensure end-to-end delay. Carrying out offline routing and scheduling configuration on TT traffic ensures the conflict-free of TT traffic in the transmission link. Since the priority of TT traffic is higher than that of RC traffic, ignoring RC traffic in the process of configuring TT traffic routing may make the RC traffic transmission delay very large, exceeding the scope of network design requirements. The issue of concern in this paper is the routing configuration for TT traffic and RC traffic in the TTE network. Under the premise of ensuring the schedulability of TT traffic, the transmission path of TT and RC traffic is configured and optimized, and the end-to-end delay of RC traffic is reduced. Through the network topology information and network traffic information, a load balancing strategy based on the genetic algorithm is used in this paper to configure TT traffic routing, and a path cost strategy is used to configure RC traffic routing. Experimental results from multiple use cases show that routing configuration for TT traffic has a great effect on the end-to-end delay of RC traffic.