摘要：Significant increasing in the number of vehicle accidents around the world and the resulting losses in both aspects human and material necessitate us to find efficient, innovative solutions to this passive phenomenon. Vehicular Ad hoc NETwork (VANET) is an emerging technology that attracts many research interests in the field of wireless communications due to its benefits in providing more road safety and enhancing traffic management. Security is one of the most critical issues that face VANETs. VANETs are vulnerable to different types of attacks as long as they are still a fertile area for attackers to compromise the network with their malicious attacks. However, to build robustness networks, a vital issue that needs to be taken into consideration is to make the networks resistant to security attacks. This paper presents an introduction to VANETs and its structure and provides an overview of fundamental security challenges and requirements in VANETs. It also discusses and investigates major security attacks and its effects on the security requirements. Afterwards, it studies, compares and finally classifies a variety of possible countermeasures that have been proposed to cope with these attacks.
