A Fuzzy Logic Based Trust Evaluation Model for IoT

Internet of Things (IoT) is a way of connecting the physical world to the internet where various devices are capable of communicating with each other. They all need a secure environment but the problem is implementation of any security approach for an IoT node is very difficult as resources of IoT nodes are very limited. So, trust evaluation and trust assessment are very important for IoT nodes. The paper proposes a fuzzy logic based trust evaluation model for IoT that employs different trust factors like End-to-end Packet Forwarding Ratio (EPFR), Amount of Energy Conversion (AEC), Packet Delivery Ratio (PDR) and Security Grade (SG) in order to construct a Fuzzy Inference System (FIS) that can calculate the trust value of each IoT node. Based on the resultant trust value, the IoT nodes are classified into three categories: Not Trustworthy, Not Sure and Trustworthy. An IoT node which belongs to Trustworthy only gets the access to forward the data packets or communicate with other IoT nodes. The Not Trustworthy and Not Sure IoT nodes are set to sleep mode for power conservation.