基于密度和距离的多跳广播转发节点选择方案

Density-distance based multi-hop broadcast forwarder selection scheme in VANET

摘要:

多数车联网VANET(Vehicular Ad Hoc Network)的安全应用均采用多跳广播方式分发安全消息。现已提出了许多的多跳广播转发节点选择方案,但它们以减少转发节点数为目的。为此,提出基于密度和距离的多跳广播转发节点选择方案DDBFS(Density-Distance based multi-hop Broadcast Forwarder Selection scheme),记为DDBFS。DDBFS方案主要解决两个问题：密集区域的冗余广播和稀疏区域的高的传输时延。在提出的DDBFS方案中,节点在决策是否转播接收的消息前,依据距离和网络密度设置定时器,一旦定时完毕,且在定时期间,没有其他节点转发该消息,该节点就成为下一跳转发节点。仿真结果表明,与现有的方案相比,提出的DDBFS协议在重播次数和传输时延性能得到显著提高。在密集区域,消息重播次数下降了约57%,在稀疏区域,传输时延缩短了约82%。

Abstract:

Most VANET (Vehicular Ad Hoc Network) safety applications use multi-hop broadcast communications to disseminate safety information. Many multi-hop broadcast forwarder selection schemes have been proposed. Their aim is to reduce the number of forwarders. In this paper, we propose a density-distance based multi-hop t forwarder selection scheme (DDBFS) to address the problems of (i) redundant broadcasts particularly in dense network and (ii) the high latency in sparse networks. We present a solution where both the distance and the network density are considered in calculating the waiting time before deciding whether to rebroadcast received messages or not. Once the waiting time is over and the messages have been not forwarded by other nodes, the node is considered as to be next-hop node. Simulation results show that our scheme achieves better performance in terms of number of rebroadcasts and dissemination delay compared to existing solutions. Our protocol results in improvement up to 57% in message rebroadcast when the network density is high, and 82% in dissemination delay when the network is sparse.