A vehicular ad hoc network (VANET) is a mobile ad hoc network that allows wireless communication between vehicles, as well as between vehicles and roadside equipment. Communication between vehicles promotes safety and reliability, and can be a source of entertainment. We investigated the historical development, characteristics, and application fields of VANET and briefly introduced them in this study. Advantages and disadvantages were discussed based on our analysis and comparison of various classes of MAC and routing protocols applied to VANET. Ideas and breakthrough directions for inter-vehicle communication designs were proposed based on the characteristics of VANET. This article also illustrates physical, MAC, and network layer in details which represent the three layers of VANET. The main works of the active research institute on VANET were introduced to help researchers track related advanced research achievements on the subject.
Keyword:
MAC
INTRODUCTIONRoad accidents have become a global public safety issue. Accidents caused by strong mass destruction have been became the number one killer in the world. Vehicle networking in an intelligent transportation system provides an important foundation to resolve this issue. Vehicular ad hoc networks (VANETs) are self-organizing networks dedicated to inter-vehicle communication and design. VANET utilizes mobile ad hoc network (MANET) technology to instigate inter-vehicle communication [1] which allows the driver to obtain the status information of other vehicles (e.g., BVR speed range, direction, position, and brake pedal pressure) and real-time traffic dispatch.The design goal of VANET is to establish an inter-vehicle communication platform that improves traffic efficiency, safety, and reliability, as well as provides convenience and multiple access to drivers and improves passenger comfort [2], [3] During the 2003 ITU-T Telecommunication Standardization Conference on cars, national car experts proposed to reduce traffic accident by 50% [4] Over 90% of the deaths occur in low-income and middle-income countries, which have only 48% of the world's vehicles, according to the Global status report on road safety more than 1.2 million people die in road accidents every year. A wireless ad hoc network is a distributed architecture with emphasis on hopping (routing), self-organization, and decentralization. VANET is defined as a fast-moving outdoor communication network [5]. It is also referred to as a self-organized traffic information system. The basic idea behind VANETs is the exchange of data and