Exploiting vehicles' reputation to mitigate DoS attack

Recently the convergence of safety and security needs in automotive systems is one of the main challenges of the research community. However, the different nature of safety and security metrics suggests that no individual assessment technique is sufficient, in isolation, to validate large systems that are intended to be both safe and secure. The introduction of new generation ICT systems into vehicles makes them potentially vulnerable to security attacks that may impact on the safety of passengers, pedestrians, and vehicle itself. Hence, entities involved in a communication have to be evaluated trustable by means of specific mechanisms of the vehicle or infrastructure system. This work aims at proposing an algorithm for the calculation of reputation of vehicles in a Vehicular Ad Hoc Network (VANET) based on the type and number of exchanged messages. The ultimate goal is to mitigate the Denial of Service (DoS) attack in such kind of communication by acting as a firewall with respect to not trustable vehicles. Indeed, the DoS is a security attack that affects the availability of network bandwidth. This may have an impact on safety of drivers and vehicles since it may prevent the communication and spread of important information for, e.g., human life.