Distributed relay selection with network coding for data dissemination in vehicular ad hoc networks

Data dissemination in vehicular ad hoc networks has been an interesting research topic since rising applications can be run and served based on the success and efficiency of data dissemination in vehicular ad hoc networks. However, the volatile vehicle density, the highly dynamic topologies, and the packet lossy nature of the vehicular wireless communications pose real challenges for vehicular ad hoc networks to achieve high-speed content downloading and efficient resource utilization. In this work, we design a collision-free distributed relay selection method, by jointly considering the geographical locations, channel conditions, moving velocities, and packets receiving statuses of vehicles, to combat the mobility and lossy channel property of vehicular ad hoc networks. Moreover, we adopt the instantly decodable network coding for the selected relay vehicle to retransmit packets which were lost in the original transmission, resulting significant improvements in both network throughput and transmission delay. Simulation results show that the proposed strategy effectively reduces the delay of data dissemination in highway scenarios and improves the downloading rate, as well as the resource utilization of wireless channels.