航空电子高速交换式网络的服务质量保证方法

Quality of service guarantee for avionics high-speed switched network

以保证航空电子高速交换式网络的实时性和高带宽为目的,提出光纤通道(FC,Fibre Channel)通信协议承载于波分复用(WDM,Wavelength Division Multiplexing)传输机制之上的架构.采用适用于实时交换的周期性数据流模型,提出了基于负载匹配的输出轮询(LOR,Load-matching Output Round)调度算法.该算法仅使用一次仲裁即可达到输入/输出的最大匹配(100%).给出LOR算法的核心代码,时间复杂度仅为O(1),易于在硬件中实现.最后通过将LOR算法嵌入到网络处理器中,注入时间敏感的负载流量,以服务质量特性(延迟、吞吐和超时消息数)为性能衡量指标进行实验,结果表明LOR算法在轻负载(30%)下,服务质量特性与经典算法(iSLIP,DRR,EDRR)基本持平;在重负载(70%)下,仅LOR算法能满足延迟的实时性要求,且LOR吞吐率高于经典算法近10个百分点,超时消息数比经典算法少了100个以上.

To achieve avionics network＇s real-time and high bandwidth performance, the fibre channel （FC） over wavelength division multiplexing（WDM） architecture was established, which adopt the periodical flows for real-time communication in switches, and the scheduling algorithm based on load-matching output port round（ LOR） was proposed. Using only once arbitration, LOR could obtain input/output port＇s maximum matching （100%）. Core code of LOR was described after that, which had O （ 1 ） complexity and could be embed into hardware suitably. Finally, the experiments were conducted at network processor under time-sensitive load in term of quality of service （QoS） parameters （delay, throughput and overtime packets number）, and the results show that under low load （30%） LOR algorithm has the same QoS performance with traditional algorithms （iSLIP, DRR, EDRR） , but under heavy load （70%） only LOR could satisfy real-time delay con- straint, and throughput of LOR is nearly more than 10% than traditional algorithms, and overtime packet number of LOR is less 100 than traditional algorithms＇.