Preventing a DoS threat in vehicular ad-hoc networks using adaptive group beaconing

In vehicular ad-hoc networks (VANETs), vehicles exchange position information with their neighbors through periodic beacon messages. In dense areas, a massive number of messages may saturate the network and prevent nodes from acquiring the proper resources to exchange their messages. As the vehicle density increases, the network will be at risk of initiating a denial-of-service attack (DoS) of its own, which will prevent the utilization of beacon messages as intended and affect other critical applications. To resolve such potential threats, adaptive beaconing can adjust a vehicle's beacon rate based on detected signal congestion and traffic conditions. In VANETs, high mobility and rapid change in vehicles' locations present challenges in detecting traffic congestion and providing secure and accurate position information. In this paper, we present a novel approach to sending beacon messages based on neighborhood awareness and road traffic density. The proposed solution also allows authority managements to reduce the number of periodic messages to provide quality of service (QoS) for specific applications and vehicles. Simulation showed network performance improvement and a reduced number of beacon messages in dense areas without compromising the level of awareness that will support QoS provisioning and allow bandwidth availability for critical applications.