摘要
对用于卫星网络传输控制协议(TCP)改进版本的TCP-Vegas,TCP-Hybla,TCP-Westwood三种拥塞控制算法网络性能进行了仿真研究。在两种实验场景中用网络仿真器和MATLAB软件分析了三种算法的吞吐量、拥塞窗口和公平性等性能。其中:第一组两个数据流的TCP拥塞控制算法相同,考验各种算法在卫星链路中单独存在时的性能;第二组以传统地面网络使用的TCP-Reno为对照数据流,考察各算法与Reno竞争时的性能。结果发现:三种算法的吞吐量均较Reno有所增大,Westwood提升最多,Hybla次之,Vegas最少;Vegas的拥塞窗口较小,Hybla,Westwood的拥塞窗口则较大;Hybla,Westwood的公平性良好,Vegas的公平性较差,甚至劣于Reno。分析为新拥塞控制算法研究提供了理论准备和仿真基础,并提出了融合各改进版本TCP优点的研究方向。
The network performances of three enhanced transmission control protocol(TCP)for satellite were analyzed through simulation in this paper, which were TCP-Vegas,TCP-Hybla and TCP-Westwood.The throughput,congestion window and fairness index of the three algorithms in two scenarios were studied using Network Simulator 2(NS2)and MATLAB software.The one scenario was that the two data flux had the same congestion algorithm,which was used for studying performance of each congestion algorithm existing alone in satellite IP link.And the other scenario was that one data flux was one of the three congestion algorithms and the other was TCP-Reno which was served as reference,which was used for studying the performance of the three congestion algorithms while comparing with TCP-Reno.It found that the throughputs of the three congestion algorithms were larger than that of TCP-Reno.TCP-Westwood was the biggest,TCP-Hybla was the second and TCP-Vegas was the least.Congestion window of TCP Vegas was small and congestion windows of TCP-Hybla and TCP-Westwood were large.Fairness index of TCP-Hybla and TCP-Westwood were good and fairness index of TCPVegas was not good even worse than that of TCP-Reno.The paper has provided a theoretical base and simulation base for developing new congestion algorithm.The research suggestion has been given for integration of various enhanced version of TCP.
出处
《上海航天》
2016年第6期109-114,共6页
Aerospace Shanghai
基金
国家自然科学基金资助(61271349
61371147
11433002)
上海航天科技创新基金资助(SAST2015039)
