一种提高802.11无线Ad Hoc网络公平性的新机制-FFMA

实现多个数据流对无线信道的公平共享是802.11无线Ad Hoc网络中的一个重要议题,但802.11DCF机制在无线Ad Hoc网络中存在严重的公平性问题,甚至有可能出现单个节点或数据流独占信道而其他节点和数据流处于"饥饿"状态的情况.论文提出了一种新颖的保证数据流间公平性的MAC层接入机制FFMA(Flow rate-based Fair Medium Access),通过公平调度和公平竞争的方式,FFMA能够在数据流间公平地分配信道带宽资源.仿真结果表明,在无线Ad Hoc网络中,FFMA可以在保证信道吞吐量的前提下取得远优于802.11 DCF的数据流间的公平性.

FFMA:A Novel Mechanism for Improving Fairness in 802.11 Ad Hoc Networks

Fair access of the shared wireless medium among different flows is an important issue in 802.11 based wireless ad hoc networks.However,due to unfairness caused by 802.11 DCF,802.11 based ad hoc networks face a severe "fairness problem".In some cases,some stations or flows may capture the whole channel while other stations or flows suffer from starvation.A novel fair medium access mechanism FFMA(Flow rate-based Fair Medium Access) is proposed in this paper.FFMA can provide a per-flow fair channel allocation by fair scheduling and fair contention.The simulation results prove that FFMA can achieve much better fairness than 802.11 DCF and guarantee a reasonable throughput performance in wireless ad hoc networks.