光突发交换网络中TCP短流的分析模型

Model for TCP short-lived flows in optical burst switching

分析了光突发交换(OBS)网络中突发传送方式对TCP短流的影响,以平均发送完成时间为主要性能指标,提出了一种OBS网络中TCP短流的分析模型,导出了一个平均发送完成时间与TCP短流长度、突发丢失率、突发组装时间以及往返时间等之间的递推表达式.仿真验证了分析的正确性,结果表明,当突发丢失率小于0.01且突发组装时间与往返时间之比小于0.1时,突发传送方式对TCP短流的性能没有影响.

In this paper, we propose a model to predict the transmission control protocol （TCP） performance in terms of the average complete time for short-lived flows in OBS networks. By analyzing the impact of burst assembly and burst dropping on the performance of TCP short-lived flows, a recursive equation is obtained, which represents the relationship between the average complete time and the size of TCP short lived flows, burst assembly time, burst loss rate and the round trip time. The correctness of the analysis is then tested by simulation. Both the results of analysis and simulation show that the transfer mode of the burst has little impact on the performance of TCP short-lived flows when the burst loss rate is less than 0.01 and the ratio of assembly time to the round trip time is less than 0.1.