一种Ad hoc网络的跨层拥塞控制改进方案

针对传统的TCP拥塞控制协议不能很好适用于无线Ad hoc网络的问题,本文利用跨层设计思想和优化理论,通过提取协议栈各层的特性参数,给出了无线Ad hoc网络跨层拥塞控制的改进方案CCIM (cross-layer control improvement methods). 提出了将MAC层输入、输出速率与网络层缓存队列长度相结合的拥塞检测新方法,并依据ECN显示拥塞反馈机制和扩展信令传递机制,对拥塞控制和随机接入进行建模,以便获取最优发送速率. NS2仿真结果表明,该方案能够降低端到端传输时延,使网络吞吐量和公平性得到了明显改善. 

A Improving Cross-Layer Congestion Control Scheme for Ad Hoc Networks

For the traditional TCP congestion control protocol did not suit wireless Ad hoc networks, techniques were applied to provide wireless Ad hoc networks cross-layer congestion control improvement scheme (CCIM), including cross-layer design, optimization theory and extracting characteristic parameter from each layer of the protocol stack. In the CCIM, a new method was presented for congestion detection, making the input/output rate of MAC layer accord with the buffer queue length of network layer, and a model of the congestion control and random access was built to get the optimal transmission rate based on the mechanism of the ECN explicit congestion feedback and the expansion signal transmission. The NS2 simulation results show that the CCIM scheme can reduce the end-to-end transmission delay, and the network throughput and fairness are improved obviously.