摘要
针对传统AODV路由协议中周期性Hello消息广播机制会造成协议效率低下的问题,提出了一种利用无线链路有效性预测来降低Hello控制报文的新策略.首先给出了适用于视距无线传输环境下新的链路有效性预测模型,根据此模型所预测的无线链路生命周期来动态更新AODV路由协议中的Hello Interval配置参数,从而实现在不同链路稳定性下以不同频率广播Hello消息的目的.仿真结果表明,相比于采用周期性Hello消息广播机制的原协议而言,改进协议有效减少了不必要的报文开销,并在平均端到端时延和协议效率这2个性能指标上都获得了明显改善.
To cope with the problem of low protocol efficiency of the standard ad hoc on-demand distance vector (AODV) routing protocol with the periodic Hello message broadcast mechanism, a new link availability prediction based strategy is introduced to reduce the amount of Hello messages. In this strategy, a novel wireless link availability prediction model under line-of-sight (LOS) propagation environments is proposed based on which the parameter of Hello Interval in AODV can be dynamically adjusted to achieve the goal of changing the frequency of Hello message broadcasts under different link stability degrees. Simulation results demonstrate that, compared with the standard AODV with the periodic Hello message broadcast mechanism, the proposed protocol effectively reduces unnecessary control message overhead and greatly improves the performance in terms of end-to-end delay and efficiency.
基金
The National High Technology Research and Development Program of China (863Program)(No2006AA01Z268)