Vehicular ad hoc networks (VANETs), which is a subclass of Mobile ad hoc networks, have recently been developed as a standard means of communication among moving vehicles because it has tremendous potential to improve vehicle and road safety, traffic efficiency. VANET applications has the characteristics such as fast change of topology, bandwidth limitation and lack of central coordinationn that causes network congestion which restricts the network performance. Number of solutions proposed to overcome these challenges and to reduce congestion on VANET. These solutions include congestion control algorithms, some of them based on maintaining the beacon load below certain threshold value by adjusting transmit power or transmit rate or both. And others are based on utility function, carrier sense threshold, prioritization or a combination of them. Hence, this study takes a closer look at existing congestion control algorithms to solve congestion problems because it affects the performance of safety messages. The study further exposes the weaknesses and advantages of some of these congestion control algorithms, which can be helpful to tackle with the problems of congestions in VANETs.

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Vanet Beacon Messages Event Driven Messages Congestion Control Ieee 802. 11p