研究了AFDX交换机在采用轮转调度策略，并保证消息传输实时性的前提下，对消息到达时间间隔抖动的容忍能力。采用实时通信中的周期性任务模型，依据实时性保证原则，推导出在已知的轮转调度策略下，交换机允许消息到达最小时间间隔，及交换机对消息抖动的容忍度的数学表达式。最后给出在给定的实时流量下，到达时间间隔抖动容忍度的计算实例，结合算例结果分析了实际情况中容忍度的意义，即容忍度越低，消息延时越容易破坏消息的实时性。

The tolerance to interval jitter of message arrival time was studied for round-robin AFDX switch when real-time message transport was guaranteed. Based on the insurance of real-time performance, periodical task model for real-time communication was used to derive the minimum interval tolerable for the switch and the mathematic expression for the tolerance to jitter. An example was given to indicate the calculation of tolerance to interval jitter at given flow. Based on its result, the significance of tolerance to interval jitter was analyzed, i.e. the less the degree of tolerance is, the easier the flow is to be affected.