A vehicle-density-based forwarding scheme for emergency message broadcasts in VANETs

With the extension of wireless technology, vehicular ad hoc networks (VANETs) provide general data transmission services and emergency warning services. To rescue more drivers from being involved in an emergency event on the road, fast emergency message propagation is an important issue in VANET studies. There are two types of multi-hop broadcasting forwarder selection schemes for emergency broadcasting, known as sender-oriented schemes and receiver-oriented schemes. The sender-oriented schemes periodically maintain neighbor information in order to choose the best forwarder before broadcasting the message, while the receiver-oriented schemes distributed elect the forwarders. In this paper, we propose a vehicle-density-based emergency broadcast (VDEB) scheme to solve the problem of high overhead in sender-oriented schemes, and long delay in receiver-oriented schemes. The simulation results show that our VDEB scheme can achieve better performance with low delay and little overhead.