中文摘要：

车载自组织网络（vehicular ad hoc networks,简称VANETs）具有网络间歇连通、节点高速移动及动态的网络拓扑结构等特性,如何有效地实现车辆间的数据传输,成为VANETs的重大挑战.现有研究工作基于历史交通流量或历史延迟预测路段当前交通状况的方法并不可靠.此外,要实现高效的数据路由传输,配置大量路边基础设施节点（deploying roadside unit,简称RSU）是一种可行方案,但通常需要额外开销.基于城市区域长时间拥有大量地上停放车辆这一事实,提出了基于停车骨干网络的数据传输策略PBBD（parking backbone based data delivery）,不需要配置任何地面基础设施,而是把地面的停放车辆组成一个虚拟的停车覆盖网络,通过该停车覆盖网实现数据的传输.为此,首先,对于每一条道路,把路边和非路边停放车辆组成一个尽可能长的停车簇,并基于这些停车簇组织城市停车骨干网络.其次,设计基于停车覆盖网络的全新数据传输算法来实现车辆间的有效数据传输.基于真实城市地图和交通数据的模拟实验结果表明,与现有的几种数据传输算法相比,PBBD能够以较低的网络传输开销和较小的传输延迟获得较高的数据传输成功率.

英文摘要：

Vehicular ad hoc networks （VANETs） are characterized by intermittent connectivity, high mobility of vehicle nodes and dynamic topology. This makes data delivery in VANETs very challenging. Pervious works that based on historical traffic pattern or historical data delivery delay to predict current traffic conditions on the roads are not accurate. Deploying roadside units （RSUs） is a possible solution to overcome the challenges, but it often requires investment. Driven by the fact that there are large amounts of outside parked vehicles in urban areas, this paper proposes a parking backbone based data delivery paradigm （PBBD） for VANETs. PBBD does not need any RSUs, but leverages a virtual overlay network formed by outside parked vehicles to help transmitting messages among vehicles. This scheme consists of two parts. First, to each road, parked vehicles both at roadside and off-street are grouped into a cluster as large as possible. An urban overlay network is established based on this type of clusters for data transmission. Secondly, novel message delivery schemes are designed to efficiently transmit messages to destination vehicles through the proposed virtual overlay network. Simulation results based on a real city map and realistic traffic situations show that PBBD achieves a higher delivery ratio with lower network transmission overhead and reasonable transmission delay.