Enhanced Switch Design Supporting Dual Preemption Under Real-Time Ethernet

Abstract

Because of the advantages of high bandwidth, low cost, and architecture openness, Ethernet is increasingly used in the industrial Internet to support both time-critical services and conventional communication services on a unified network infrastructure. The biggest challenge right now is to provide low and deterministic latency for time-critical services. Preemption is an effective way to achieve deterministic and low latency. However, the current preemption mechanism has no specific hardware implementation, nor does it describe the restoration after preemption. In this paper, we implement preemption mechanism in hardware and propose two preemption restoration mechanisms: Preemption Restart and Preemption Resume, they are suitable for different scenarios. We also discussed all the details implemented on common commercial switch architectures. Finally, we implement preemption restoration and verify our design in the actual vehicle network topology. Through experiments, we verify the necessity of the preemption mechanism and evaluate the impact of preemption restoration on non-time-critical services.