基于邻居覆盖信息和节点移动速度的无线自组网多播方案

A wireless ad hoc network multicast scheme based on neighbor coverage information and node motion velocity

针对无线自组网节点的移动导致多播可靠性降低、开销和时延增加的问题,提出基于邻居覆盖信息的多播方案。该方案通过少量的Hello报文收集一跳内的邻居信息,并据此实时计算节点的密度系数、邻居节点未覆盖率等参数,利用所获参数动态调整节点的多播数据转发时延与转发概率。为进一步降低时延,提出一种基于节点移动速度的数据分发方案,它允许部分快速移动节点采用更高的概率转发多播数据。将其扩展至多播方案中,形成基于邻居覆盖信息和节点移动速度的多播方案。NS2的仿真结果表明,与现有方案相比,该方案将分组投递率提高27%,控制开销减少33.2%,并将端到端平均时延降低45%。

A multicast scheme based on neighbor coverage information is proposed to solve the problems of multicast reliability decrease,overhead increase and latency increase caused by node mobility in wireless ad hoc networks.In the scheme,the one-hop neighbor information is collected by using a few Hello messages,and accordingly,parameters such as node density coefficient,and uncoverage rate of neighbor nodes are calculated in real time.The obtained parameters are used to dynamically adjust the forwarding time delay and forwarding probability of nodes' multicast data.A data distribution scheme based on node motion velocity is proposed to further reduce the time delay.The scheme allows part of fast mobile nodes to perform multicast data transmission with a higher probability.A multicast scheme based on neighbor coverage information and node motion velocity is formed by extending the data distribution scheme to the multicast scheme.The results of the simulation with the NS2 show that the proposed scheme can improve the packet delivery rate by 27%,and decrease the control overhead by 33.2% and the average end-to-end delay by 45% in comparison with the existing schemes.