通过ARQ提高无线网络中的TCP吞吐量

针对现有提高无线网络中传输控制协议（TCP）吞吐量方案（如Snoop）的若干局限性，提出一种改进方案，利用数据链路层的自动请求重传（ARQ），检测并重传在无线链路上丢失的分组，从而提高TCP的吞吐量性能，这一方案不需要修改端终点的TCP实现，与Snoop相比，ARQ可以传输加密或封装后的分组，不受TCP确认机制的影响，不要求基站保留TCP流的状态，降低了基站的实现复杂度，仿真结果表明，当链路错误率较高或网络中存在竞争性背景流量时，ARQ可以比Snoop更加有效地提高TCP吞吐量。

Improvement of TCP Throughput in Wireless Networks by ARQ

A new approach to improve transport control protocol (TCP) throughput in wireless networks was proposed, in which the detecting and retransmission of lost packets are performed by ARQ (Automa tic Repeat ReQuest) in data link layer. Compared with Snoop, a typical one of proposed solutions, ARQ adapts to the transmission of encrypted or encapsulated packets and is hardly affected by TCP's acknow ledgment policy. The complexity introduced here by ARQ in base stations is less than that of Snoop, because in ARQ the base stations need not save the state of every TCP flow. The simulation results show that if the link error rate is high, or there is competing traffic in the network, ARQ is more effective than Snoop for improving TCP throughput in wireless networks.