TruSD: Trust framework for service discovery among IoT devices

Abstract

IoT provides an environment which enables access to a plethora of different services. In order to reach these services, devices need to decide if the providers are trustable or not. The decision to trust a node with whom one has not communicated earlier becomes more critical when the system has unrecoverable damages with inaccurate services. In this paper, we propose a framework which enables trusted communication among devices during service discovery. It focuses not only on the communication between the known devices but also the stranger communications which have not contacted earlier. Our framework works in a decentralized manner on top of a structured P2P network based on a Distributed Hash Table (DHT). In our system, for each device there are several nodes which are responsible for holding a trust value for this device. These responsible nodes are called Reference Holders for this device. By utilizing DHT, we propose a novel way of choosing Reference Holders that prevents the malicious nodes to control these nodes. Our protocols provide trust aggregation, service provision and feedback aggregation. In our threat model, attacker provides on-off, bad mouthing, ballot stuffing and selective attacks. We present closed form of probabilistic analysis and provide simulations that manage to give network-wide probabilistic security guarantees. Our results suggest that until 60% of the devices are captured, the results are perfect. Also, just three reference holders are enough to get accurate services through the network. Additionally, we analyze the framework in terms of memory, computational cost and communication overhead since we propose the framework for IoT devices. Due to these analysis, our framework is affordable for IoT devices.