Abstract
Reducing the number of road accidents is a key agenda item for governments across the world. This has led to an increase in the amount of attention given to Vehicular Communication Systems (VCS), which are seen as an important technology that can offer significant improvements in road safety. Using VCS, vehicles can form a dynamic self-configuring network that enables a vehicle to communicate with other vehicles (V2V) and roadside infrastructure (V2I). However, such wireless communication channels are vulnerable to attacks, and therefore an authentication scheme for communications should be designed before the deployment. Prior work has focused on utilising digital signature approaches to achieve the security requirements, but due to the special characteristics of VCS, such approaches are not well suited for safety related applications of VCS, since they incur high communication and computation overheads. To combat this issue, we propose a certificateless and lightweight authentication scheme to provide means of secure communications for VCS. In this work we introduce authentication tokens, which replace digital certificates to reduce the burden of certificate management on a Trusted Authority (TA). In addition, the utilisation of tokens ensures that mutual authentication is achieved for V2I communication. Moreover, we employ TESLA as the underlying broadcast authentication protocol to achieve the required security goals for safety message broadcasting. According to the security analysis and extensive simulation of our scheme, the results show that it can withstands various types of attacks. Also it has better performance in term of verification delay, scalability and communication overhead compared to lightweight authentication schemes that are based on similar techniques. Therefore, the scheme is well suited for VCS