城市环境下的一种车辆自组织网络机会路由协议

An opportunistic VANET routing in urban environment

车辆自组织网络(vehicular ad-hoc networks,VANET)的拓扑结构具有高动态性,设计适应其高速变化的路由协议具有很大挑战性。提出采用机会转发方式的地理位置路由协议,将每次转发的单一目标节点改进为一个集合,以降低高速变化的拓扑导致的节点接收数据失败的概率。提出了一种新颖的转发集构成方案,改进了传统的由数据包携带转发集的做法,将转发集合的计算和确定分布到每个接收节点,在很大程度上减少了路由控制信息开销。提出了一种动态的转发节点选择机制,并引入了对实时交通状况的考虑,在一定程度上依据实时交通密度选择转发路径,能有效应对车辆自组织网络连接不稳定性。仿真结果表明,所提出的路由协议在包投递成功率、端到端传输时延和归一化路由开销等方面都取得了较好的路由性能。

The topology of vehicular ad-hoc networks is highly dynamic,so the designing of adaptive routing protocols still faces great challenges.This paper proposes a geographical routing protocol based on opportunistic forwarding,which uses a target set instead of a single target node when forwarding packet.It improves the traditional data forwarding mode and adapts better to the rapidly changed connection states between vehicles.In this paper,a novel scheme to construct the forwarding set is proposed,which improves the traditional packet piggybacked forwarding set.The determination of the forwarding set is distributed to each of the receiving nodes,rather than being piggybacked it by every data packet.This improvement can greatly reduce the overhead of routing control information,and subsequently improves the performance of routing protocols.This paper proposes a dynamic node selection mechanism,and takes into account the real-time traffic density,which can effectively cope with the topological instability caused by high-speed moving of vehicle nodes.Simulation results show that the proposed routing protocol achieves a good routing performance in terms of packet delivery success rate,end-to-end delay and normalized routing overhead.