LEO卫星网络中TCP协议性能研究

在低地球轨道卫星网络中，星地切换会造成数据包丢失，导致应用于地面有线网络中的TCP协议产生盲目快速重传，从而削弱TCP协议性能。针对该问题，在异构网络边界处加入性能增强代理模型，通过阈值调节发送速率，屏蔽切换对源端的影响。理论分析和仿真实验表明，在不同误码率情况下，该方法的平均吞吐量优于常规TCP，可避免短时间内由连续切换和误码造成的TCP性能下降。

Research of TCP Protocol Performance in LEO Satellite Network

In Low Earth Orbit(LEO) satellite network, channel handover between satellite and ground causes packets loss to make TCP protocol applied in wired network blindly to generate fast retransmission and weaken the performance of TCP protocol. Aiming at this problem, this paper adds Performance Enhancing Proxy(PEP) model in heterogeneous network, PEP shields the channel switching effect to the source by changing the value of watermark. Theoretical analysis and simulation experiment show that this method brings higher throughput than common TCP with different error rate, and it can avoid the TCP performance decreasing caused by continuous channel switching in short period.