车载时间敏感网络链路冗余调度性能分析

TSN协议中802.1CB协议是保障车载以太网网络可靠性的重要角色，其通过链路冗余确保报文的稳定传输，而不同冗余链路间的传输特性不一致可能会对后续流量调度产生影响，因而需要探讨链路冗余对调度性能影响。本文从汽车网络拓扑冗余结构出发，分析了冗余协议和调度协议的关联性，并探讨了链路冗余对802.1Qbv分时调度机制以及802.1Qch循环队列与转发机制的影响。最后本文构建了链路冗余调度性能评价模型，并基于OMNeT++平台和实物验证平台，对上述影响进行仿真验证。结果表明链路冗余产生的冗余流量抵达间隔和链路跳数差异分别对802.1Qbv和802.1Qch有显著影响，另外需要关注冗余拓扑中网桥端口速率变化所带来的影响。

Analysis of time-sensitive network link redundancy scheduling performance

The 802. 1CB protocol in the TSN protocol plays an important role in ensuring the reliability of the in-vehicle Ethernet network. It ensures the stable transmission of packets through link redundancy, and the inconsistency of transmission characteristics between different redundant links may affect subsequent traffic scheduling. Therefore, it is necessary to explore the impact of link redundancy on scheduling performance. This article starts from the topology redundancy structure of automobile network, analyzes the correlation between redundancy protocol and scheduling protocol, and discusses the influence of link redundancy on 802. 1Qbv timeaware shaper mechanism and 802. 1Qch cyclic queuing and forwarding mechanism. Finally, we establish a link redundancy scheduling performance evaluation model, based on OMNeT++ and hardware verification platform. We simulate and verify the above effects. The results show that the difference in the arrival interval of redundant traffic and the number of link hops caused by link redundancy has a significant impact on 802. 1Qbv and 802. 1Qch, respectively. In addition, it is necessary to pay attention to the impact of changes in the rate of bridge ports in redundant topology.