卫星互联网TCP拥塞控制算法

摘要

为解决TCP Vegas拥塞控制算法无法适应卫星互联网场景的问题,分析该问题导致吞吐量性能降低的原因,提出一种基于链路长度计算结合带宽估计判决的Vegas-W算法.通过计算通信链路长度修正往返时延,结合带宽估计判决增加带宽竞争力,使Vegas拥塞控制算法在时延突变的情况仍保持较高吞吐量,适应卫星互联网星座动态环境特点.NS2仿真结果表明,Vegas-W算法相比Vegas算法在卫星互联网场景中吞吐量性能提高了40％,有效降低时延突变和带宽竞争不足给Vegas算法造成的不利影响.%To solve the problem that the TCP Vegas congestion control algorithm can not adapt to the satellite network scene,leading to compromise the throughput performance,the causes of the problems were analyzed,and a Vegas-W algorithm based on link length calculation and bandwidth estimation was proposed.Round trip delay was fixed by calculating the length of the communication link and the bandwidth competitiveness was increased using the bandwidth estimation,which made the Vegas congestion control algorithm maintain the high throughput in the case of the delay mutation to adapt to the dynamic environment of the satellite Internet constellation.NS2 simulation results show that Vegas-W algorithm improves the throughput performance by 40％ compared with the Vegas algorithm in the satellite Internet network,effectively reducing the adverse effects on the Vegas algorithm caused by delay mutation and bandwidth competition.