软件定义车联网的数据转发策略和路由选择技术

针对目前车联网（VANET）数据转发效率低的问题，提出了软件定义网络（SDN）的数据转发策略和路由选择技术。首先，采用了软件定义车联网的分层控制结构，由局部控制器和全局控制器组成，实现数据转发和控制分离，可灵活控制数据转发的方向；然后，设计了单条路段的车辆路由机制，该机制预测车辆节点位置并采用贪心策略，实现数据的稳定传输；其次，设计了多个需求间的路段路由机制，该机制采用广度优先搜索（BFS）算法和边集相结合的方式，实现多个需求间路径不相交，缓解带宽瓶颈问题；最后，通过仿真验证，对比无线自组网按需平面距离向量（AODV）路由，所提出的数据转发策略和路由选择算法在数据分组接收率上提高40%以上，平均延迟时间降低60%左右。实验结果表明，软件定义车联网的数据转发策略和路由选择技术能够提高数据转发效率，减少平均收包延时。

Technology on data forwarding and routing selection for software defined vehicular Ad Hoc network

Since the data forwarding in Vehicular Ad Hoc Network (VANET) is inefficient, a technology on data forwarding and routing selection based on Software Defined Network (SDN) was proposed. Firstly, a hierarchical architecture of SDN based VANET, which was consist of local controller and global controller, was used to separate data forwarding from transmission control and decide the direction of data forwarding flexibly. Secondly, a vehicular routing mechanism of single road section was designed and data could be transmitted stably by predicting vehicular position and using greedy strategy. Thirdly, to achieve the goal of path disjoint which could avoid the bandwidth bottleneck between multiple demands, a road section routing mechanism was proposed, which combined the Breadth First Search (BFS) and edge set. Finally, compared with Ad Hoc On-demand Distance Vector (AODV) routing, the proposed algorithm could increase data reception rate by 40% and reduce average delay by 60%. The simulation results show that the technology on data forwarding and routing for software defined VANET can effectively improve the data delivery rate, and reduces the average packet delay.