An Effective Location-Based Alert Messages Dissemination Scheme for Software Defined Vehicular Networks.

Software Defined Networking (SDN) is considered as a key paradigm for future vehicular networks and its adoption may pave the way to novel approaches to support emerging and legacy ITS services, such as Alert Message (AM) dissemination. Historically, to meet the low dissemination delay requirements and full vehicle coverage, Vehicular Ad-hoc NeTworks (VANETs) were considered as the underlying assumption of most proposed AM dissemination schemes. With SDN, vehicular-to-infrastructure (V2I) links are a viable alternative that adds to Vehicle-to-vehicle (V2V) links. Moreover, a global view of the network at a centralized controller complemented with information on vehicles and their route helps to adjust the dissemination procedure to improve its performance and efficiency. In this paper, we propose a location-based AMs dissemination scheme that combines V2I broadcasts with V2V rebroadcasts in order to provide a low delivery delay, very limited collisions, high information coverage with insignificant signaling and network overhead. The originality of our scheme stands in the selection process of V2V rebroadcasts which is based on vehicles’ location with respect to predefined rebroadcast points selected by the controller. Our proposal is evaluated and compared to legacy techniques. It shows significant improvements in delivery delays and network resource utilization.