摘要
研究了移动Ad Hoc网络中的媒体接入控制问题.首先,基于IEEE 802.11媒体接入控制协议,提出了应用于MANET网络媒体接入控制的2个机制:自适应回退窗转发优先机制(FPF)和多跳链邀请发送机制(MFCTI).FPF机制根据业务优先级自适应调整竞争窗大小,而MFCTI机制则充分利用了网络层路由信息和无线传播的广播特性.在此基础上对所提出的机制进行了仿真研究并与原IEEE 802.11媒体接入控制进行了比较.结果表明,所提机制可以有效地提高网络吞吐率,降低端对端迟延,缓解网络局部拥塞,从而提高了MANET网络的性能.其另一优点是只需对IEEE802.11媒体接入控制作少量的补充和改动.
The medium access control (MAC) issue was discussed in mobile Ad Hoc networks (MANETs). Based on the IEEE 802.11 MAC protocol, this paper proposed two schemes, the forward-packet-first (FPF) scheme based on the adaptive backoff contention window and multihop forward chain transmission by invitation (MFCTI) scheme. In the FPF scheme, the contention window was adjusted adaptively according to the traffic priority. Route information and the broadcast characteristic of radio were utilized in MFCTI scheme. The performance of these schemes was studied in multihop environments by simulations. The results showed that the proposed schemes could improve the network throughput, reduce the end-to-end average delay, and mitigate local congestion effectively. Another attractive feature was that the schemes could be implemented with minor modifications to the IEEE 802.11 MAC.
基金
TheNationalNaturalScienceFoundationofChina(No.60372054).
