改进的无线网络自适应传输控制协议

摘要

Performance of Transmission Control Protocol(TCP) and utilization of the network resources is low when the TCP operates in wireless data communication.Aiming at this problem,this paper proposes an improvement algorithm of TCP to adapt the wireless environment.The data sender adopts available bandwidth estimation algorithm in order to optimize slow start threshold and congestion window,and cooperates with the router which is configured with the function of Explicit Congestion Notification(ECN)to distinguish the characteristics of packet losses.At the same time,the sender takes advantage of the wireless packet loss rate estimation to adjust the TCP segment size adaptively.Simulations results show that the throughput of modification of TCP outperforms TCP-Jersey by 30％,and TCP_SACK by 59％ approximately when the bit error rate is 1E-4.%传输控制协议(TCP)用于无线数据传输时性能较差,且网络资源利用率低.为此,提出一种自适应无线环境的TCP改进算法.在数据发送端采用带宽估计算法优化慢启动阈值和拥塞窗口尺寸,与具有显式拥塞通知的路由器配合区分分组丢失性质,同时实时监测误码丢包率,并根据监测结果自适应调整TCP段尺寸.仿真结果表明,改进的TCP的吞吐量在误码率为1E-4时高于TCP-Jersey近30％,高于TCP SACK近59％.