FROST: Friendship and Ordered Semirings Based Trust System for Securing Wireless Distributed Networks

In wireless distributed networks, reputation system plays an important role in giving distributed entities incentives to cooperate in packet forwarding. However, reputation system itself is vulnerable to attack and the reputation of entities in networks can be manipulated intentionally by malicious ones. In a previous work, Theodorakopoulos and Baras [1] develop a novel formulation of trust computation based on ordered semirings. In this paper, we adapt their ordered semirings based approach to support group trust calculation accuracy. In addition and more importantly, we use friendship model with trust fusion to decrease the overhead while maintaining the trust system. As far as we know, this is the first time notion—trust fusion is introduced in this research field. Moreover, we develop a more efficient decaying model to enable the reputation system to be more adaptive to the changing environment. Particularly, the newly proposed reputations system is employed in fully wireless distributed mobile ad hoc networks. Through theoretical analysis and emperimental results, we demonstrate that our adaptive FRiendship and Ordered Semirings based Trust system (FROST) has a good performance and can quantitatively measure reputation and defend reputation system against malicious attacks.