A Review of Congestion Control Algorithm for Event-Driven Safety Messages in Vehicular Networks

Congestion control algorithm in Vehicular Ad-hoc NETworks (VANETs) has been extensively studied. However, most of congestion control algorithms are not directly applicable to uni-priority of event-driven safety messages. The event-driven safety messages have stringent requirement on delay and reliability. The uni-priority of event-driven safety messages are caused by the traffic of the same priority, typically the warning messages of safety applications from different transmitters. The uni-priority messages should be scheduled before the node starts the transmitting process. In dense network, a large number of vehicles broadcast a beacon messages at a high number of frequency.