摘要
在有线网中,数据包的丢失一般是由网络拥塞所引起的,但在无线网络中,数据包的丢失通常是由于很高的误码率和无线链路故障所造成的。很显然,把作用于有线网络的TCP协议直接用于无线网络是不合适的。提出一种端到端自适应机制,允许TCP动态调整TCP会话的RTO(重传超时),服务器将根据客户端的反馈来调整定时器。该机制通过仿真验证,并与原始TCP协议进行比较,结果表明:由于超时次数的减少,服务器端重发的概率大大降低,无线接入点的拥塞明显改善。
In the wired network, the loss of data packets is generally caused by the network congestion, however, in wireless networks, the loss of data packets is usually due to the high bit error rate and wireless link failures. Obviously, it is not appropriate to use the TCP protocol acting on a wired network directly for a wireless network. Proposes an end to end adaptive mechanism that allows the TCP session to dynamically adjust the RTO（Retransmission Timeout） of a TCP session, the server will have to adjust the timers based on feedbacks from clients. The mechanism is verified by simulation and compared with the original TCP protocol. The results show that the probability of retransmission of the server is greatly reduced due to the decrease of the number of timeouts, and the congestion of the wireless access point is obviously improved.
