Recent advances in wireless communication technologies and auto-mobile industry have triggered a significant research interest in the field of VANETs over the past few years. Vehicular Network consists of vehicle-to-vehicle (V2V) and vehicle-to-infrastructure (V2I) communications supported by wireless access technologies such as IEEE 802.11p. This innovation in wireless communication has been envisaged to improve road safety and motor traffic efficiency in near future through the development of Intelligent Transport Systems (ITS). Hence, government, auto-mobile industries and academia are heavily partnering through several ongoing research projects to establish standards for VANETs. The typical set of VANET application areas, such as vehicle collision warning and traffic information dissemination have made VANET an interesting field of mobile wireless communication. This paper provides an overview on current research state, challenges, potentials of VANETs as well the ways forward to achieving the long awaited ITS.Keywords: Vehicular communication, V2V, V2I, ITS, IEEE 802.11p, WAVE, IEEE 1609.
IntroductionRoad accidents has been on an alarming increase despite the introduction of several innovative in-vehicle safety-oriented devices such as anti-locking braking system (ABS), seatbelts, airbags, rear-view cameras, electronic stability control (ESC). Several studies have maintained that 60% of the accidents that occur on motorways could be avoided if warning messages were provided to the drivers just few seconds prior to moment of crash [1] [2].The possibility of direct exchange of kinematic data between vehicles over an ad-hoc network environment called a vehicular ad-hoc network (VANET) has been widely perceived by governments, car manufacturing industries and academia as a promising concept for future realization of intelligent transportation system (ITS) thereby achieving safety and efficiency in our nearly overcrowded motorways. The VANET is a sub-class of MANET where the mobile nodes are vehicles. When compared with Mobile Ad-Hoc Network (MANET) and other cellular systems, inter-vehicle communication (IVC) has four major advantages: broad coverage area, relatively low latency due to direct wireless communication, little or no power issue as well as no service fees.In the recent years, car manufacturing industries, academia and government agencies have started putting much joint efforts together towards realizing the concept of vehicular communications in wide scale. Some frameworks are already worked out with the first landmark of standardization processes made by US Federal Communications Communication (FCC) [15] adopted an amendment of the legacy IEEE wireless LAN standard done by an IEEE Task Group (TG). The amendment is denoted by IEEE 802.11p as the platform for Wireless Access in Vehicular Environment (WAVE) which will be used to enable wireless communications between moving vehicles within a coverage distance of 1000m in a free space (i.e. highway scenario) and 300m in non-free space (i....