True: A Trust Evaluation Service for Mobile Ad Hoc Networks Resistant to Malicious Attacks

Trust evaluation is an essential service to ensure reliability on security relationships on networks, including Mobile Ad Hoc Networks (MANETs). However, the implementation of an effective trust evaluation service is very difficult in these networks, due to their dynamic characteristics. Though many trust evaluation services for MANETs can be found in the literature, they were not designed considering malicious attacks or were not evaluated under these attacks. This work presents TRUE, a distributed trust evaluation service for MANETs which creates a self-organized context-based trust network. To estimate the trustworthiness of other nodes, nodes form trust chains based on behavior evidences maintained within the context-based trust network. Periodically, nodes exchange trust information with the neighbors, providing an efficient method to disseminate these information through the network. Simulation results show that TRUE is very efficient on gathering evidences to build the trust networks, maintaining a small communication and memory overhead. Further, it is the first trust evaluation scheme evaluated under bad mouthing and newcomers attacks and it maintains its effectiveness in such scenarios.