A fault-tolerant broadcast protocol for reliable alert message delivery in vehicular wireless networks

In this paper, we focus on the alert message dissemination in vehicular wireless networks. Generally, the flooding method is adopted to disseminate the alert message on highway. But the flooding method may cause the alert message redundancy, which may lead to broadcast storm problem. In this paper, we propose a fault-tolerant broadcasting protocol for disseminating the alert message on highway. The proposed protocol designates two vehicles which are the farthest and sub-farthest vehicles in the transmission range of the source vehicle as the relay candidates. In addition, we propose an exponential back-off method that can effectively reduce the number of alert messages. Finally, we implement the proposed protocol in the NS-2 simulator. The simulation results show that our proposed protocol not only reduces the number of the alert messages but also decreases the transmission delay of the alert messages and increases the reliability of system.