AFDX网络端到端时延分析方法

Analysis Method of End-to-End Delays on an AFDX Avionic Network

针对AFDX网络时延分析问题,研究应用确定性网络演算理论的端到端AFDX网络传输时延分析方法。建立AFDX网络数据传输元模型,确定数据帧网络传输的各个网络元件,分析数据帧传输路径上各网络元件的最大处理时延,累加计算获得整个网络的端到端最大时延。多路复用排队时延是主要的可变时延,也是AFDX网络时延分析的关键。针对典型的先进先出策略和静态优先级排队复用策略,基于网络演算理论,给出其最大时延计算方法。最后,对该方法进行实例分析,表明该方法能够有效计算AFDX网络最差情况下的端到端数据传输时延。

Inspired by the Response Time Analysis （RTA） technique, this paper presents a new method for the estimation of end-to-end delay bounds in AFDX networks. The method is based on the theory of deterministic network calculus. Firstly, the model of data frame element transmission is provided, which determines each network node for network transmission. The longest delay of each node along the transmission path is analyzed, thus the end-to-end delay bounds can be calculated by adding of transmission delay of each node. The queuing delay of multiplexing is the main variable delay, which is affected by net configuration and multiplexing rule. The methods for analyzing delay of first-in first-out strategy and static priorities strategy are described in detail. Finally, an example is provided, which shows that the method is effective for analyzing delay bounds of AFDX.