A fuzzy fully distributed trust management system in wireless sensor networks

Wireless sensor networks (WSNs) usually consist of many tiny sensor nodes and a Sink. Problems like nodes’ misbehavior due to malicious, compromised or selfishness intentions, and WSNs’ security vulnerabilities against different attacks due to free and unprotected communications, untrusted and broadcasted transmissions, hostile environments and limited resources, degrade the security and overall performance of WSNs. In another direction, most of the traditional security mechanisms are unsuitable for WSNs. One significant security solution against these problems is Trust Management System (TMS); TMS enhances the security by detecting the nodes’ abnormal behaviors; it improves the cooperation between nodes and increases the network performance. But, existing Trust Management Systems (TMSs) have weaknesses such as high overhead and computational complexity, resources’ severe consumed and inconsistency with the especial characteristics of WSNs like limited resources, high density, dynamic topology and nodes’ mobility. As a result, this paper proposes a fuzzy fully distributed TMS for WSNs, called DTMS. It is different from other existing TMSs in terms of the fuzzy-nature trust calculation criteria, trust calculation procedure and trust forecasting capability. Finally, the performance of DTMS is compared with the performance of PowerTrust and RFSN TMSs; results of simulations and statistical analyses indicate that DTMS is improved in terms of energy consumption, accuracy, scalability and fault tolerance, and execution speed.