基于FGN输入流的G/D/1排队模拟

传统的排队理论不适于分析高速网络表现出的自相似流量.通过实验仿真,主要考察平均等待时间和在队列分别为无限和有限情形下的队列尾部特征等参数,并对以FGN为输入流的G/D/1排队模型作了定性分析.结果表明在输入流的强度和方差基本相等且系统利用律大于某一阈值的情况下,队列平均等待时间随Hurst参数增大而显著增长.同时指出在相同的条件下考察队列尾部特征,具有有限队列长度的G/D/1排队模拟结果要远优于无限队列长度下的理论分析结果.

GD1 Queuing Simulation with FGN Input

The traditional queuing theory is not applicable to the self similar high speed network traffic. A qualitative analysis of G/D/1 queue with FGN input by computer simulation was presented, and attention was focused on the average delay time and the tail behavior of infinite and finite queues. The effect of Hurst parameter was proven through these experiments that the average delay time rises evidently when Hurst parameter increases, while the input intensity and variance are almost equivalent and the utilization rate is above a certain threshold. Moreover, concerning the tail behavior under same conditions, the simulation results of the G/D/1 model with finite buffer are much more optimistic than the theoretical results of such model with infinite buffer.