MANET中TCP性能改进研究

TCP是为有线网络所设计的，其拥塞控制机制中，假设丢包是由网络拥塞造成的这一结论在MANET中不再适用。MANET中的高信道误码率，路由频繁中断等因素都会造成丢包。TCP错误的将所有丢包事件都当作拥塞处理，造成了传输性能的极大下降。文中首先总结了MANET中导致TCP传输性能下降的主要原因，然后对现有的一些典型TCP改进方案进行了讨论，最后对这些技术方案进行了比较，并指出今后研究的重点。

Study on TCP Performance Improvement over MANET

TCP is originally designed for wired networks, and the TCP congestion control mechanism assumes that all packet loss is caused by congestion. This assumption is no longer applicable in MANET, because high bit error rate and movement of nodes would also cause packet loss. The TCP＇ s poor performance in MANET is principally due to the fact that TCP makes all non congestion packet loss as congestion packet loss. This paper first summarizes several major causes for the decline of TCP performance in MANET, and then analyzes some popular TCP enhancement schemes. Finally, comparison of these schemes is proposed, and some new research direction for improving TCP performance in MANET are suggested.