带有输入和输出队列的交换结构性能研究

Analysis of Switches With Input and Output Queueing for Self-Similar Traffic

用 FGN模型驱动仿真方法 ,研究了自相似业务对带有输入、输出队列的交换机的丢包率性能的影响 .实验结果表明 ,在一定的丢包率下 ,自相似业务需要的缓冲区长度要比传统排队论模型所需长度大得多 ;增加输出缓冲区长度可以极大地改善性能 ,但是 ,增加输入缓冲区长度并没有显著地提高性能 ,这是由于输入队列队首阻塞和到达业务的自相似性的联合效应所致 .这些结果对下一代交换机的设计具有重要的意义 .

This paper studies the effect of self similar arrival processes on the packet loss performance of switches with input and output queues.Based on the FGN model driven simulation method,the experimental results show that the effect of self similarity on the buffer requirements for a desired packet loss probability is much greater when compared to the estimated requirements under the conventional geometric model.In addition,increasing the output buffer size achieves a considerable performance improvement.With input queuing,the improvement is not noticeable due to the combined effect of HOL blocking and the self similarity of arrivals.These results will likely play an important role in the design of switches.