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.

Vehicular Ad Hoc Network (VANET) is a highly dynamic communication network, which means it's a great challenge to design a stable data dissemination mechanism. Applying Named Data Networking (NDN), which focused on the content of the data, to VANET could effectively relive the problems brought by the frequent change of network topology. Firstly, the message types and data structure of NDN were improved. Secondly, the way of establishing routes according to section was put forward with the combination of characteristics of VANET so as to reduce the cost of data dissemination. The simulation results show that compared to the traditional NDN algorithm which is applied to VANET data dissemination, Average Hit Rate (AHR) and Average Forward Times (AFT) can be significantly improved by VANET data dissemination mechanism based on NDN. Therein, the average increase of AHR is about 53 percent points, while the average reduction of AFT is about 0.4 times. Therefore, the improved VANET data dissemination mechanism can improve the efficiency of data dissemination by using the new routing method.