Secure IoT Interactions using Dynamic Trust Assessment

Establishing trust-based interactions in heterogeneously connected devices appears to be the prominent mechanism in addressing the prevailing concerns of confidence, reliability and privacy relevant to secure interactions among connected devices in the network. Trust-based assessment of device legitimacy is evolving, in view of the dynamic and heterogeneous nature of IoT devices and emerging adversaries. However, computation and application of trust level in establishing secure communications, access control and privacy domain are rarely discussed in the literature. With an objective to compute trust, based on the quality of service, direct interactions, and the relationship between devices, we introduce a multi-factor trust computation model that considers into account the multiple attributes of interactions in an IoT network of heterogeneous devices providing a wide range of data and services. Direct trust is estimated for quality of service considering the response time, reliability, consistency, and integrity attributes of devices. The credibility of computed trust over time is influenced by the time decay factor. The policy-driven mechanism is employed to sift the devices and isolate the malicious ones. Extensive simulations are carried out using Contiki’s Cooja simulator for IoT networks and the effectiveness of the proposed model is tested.