RTEAM: Risk-Based Trust Evaluation Advanced Model for VANETs

In Vehicular ad hoc networks (VANETs), vehicles share and exchange information regarding road safety and traffic conditions. Thus, trust is established among vehicles to ensure the integrality and reliability of the received reports. Ensuring the security of VANETs is the key to enhance road safety, and for this purpose, several trust establishing, evaluation, and management models have been proposed. When a vehicle receives conflicting reports about an event such as a car accident from its neighboring vehicles, the receiving vehicle must decide which report has to follow. Therefore, the vehicle takes advantage of the available data about the report’s sender. Then, the vehicle takes the right action. To this end, we propose a Risk-based Trust Evaluation Advanced Model (RTEAM) based on Multifaceted Trust and Hop-based trust to take action. The proposed model provides a decision-making process according to the risk estimation for each required action of both reports (i.e., reports that deny or confirm the event). The risk is estimated according to the likelihood of taking an incorrect action and its associated impact. Finally, a decision is made corresponding to the action with the lowest risk. The experimental results show that the proposed model shows that the risk-based trust model outperforms a purely trust-based model in terms of undefined cases and true positive rates.