A Cluster-Based Beaconing Approach in VANETs: Near Optimal Topology Via Proximity Information

A key component for safety applications in Vehicular ad-hoc network (VANET) is the use of periodic beacon messages which provide vehicles with a real-time vehicle proximity map of their surroundings. Based on this map, safety applications can be used for accident prevention by informing drivers about evolving hazardous situations. In order to allow synchronized and cooperative reactions, the target of this work is to design a beacon dissemination process that provides a real-time, broad and coordinated map under the challenging VANET conditions. To this end, we propose an aggregation-dissemination based scheme for a beacon dissemination process based on inter vehicle communication. We present our proposed scheme in a set of two papers. In this first one, we propose the Distributed Construct Underlying Topology (D-CUT) algorithm tailed specifically to provide an optimized topology for such beacon dissemination process. To deal with the heavy load of beacon messages required for an accurate and broad map, we propose a topology that allows the execution of extensive but reliable spatial bandwidth reuse. Our D-CUT algorithm exploits the real-time and coordinated map for constructing an adaptive and robust topology to deal with the dynamic nature of the VANET environment. We present theoretically provable bounds demonstrating the ability of the algorithm to deal with the dynamic nature of the VANET environment supported by simulation results. In our second paper, we present a communication system design that uses this optimized topology as the infrastructure for efficient and reliable beacon dissemination process. 1 Introduction Vehicular ad-hoc network (VANET) is a promising branch of traditional MANET. VANET is designed to provide wireless communication between vehicles and between vehicles and nearby roadside equipment. This communication intends to improve both safety and comfort on the road. VANET has a number of difficulties regarding the traditional MANET. Due to the dynamic nature of VANET environments, configuration is always changing, where links may appear and disappear very quickly and vehicle density is constantly changing. On the other hand, VANET has some inherent advantages over the traditional MANET. It is generally assumed that vehicles will be aware of their own geographical position. In addition, vehicles in a VANET environment move in an organized fashion within the constraints of traffic flow. A key component in safety applications are the periodic beacon messages which provide vehicles with a broad and accurate vehicle proximity map of their surroundings. Based on this map, safety applications – usually referred …