Abstract
We propose and analyze a 3-tier cloud-cloudlet-device hierarchical trust management protocol called IoT-HiTrust for large-scale IoT systems. Our mobile cloud hierarchical trust management protocol allows an IoT device to report its service experiences and query the trustworthiness of another IoT device for service composition and selection following a simple localized report-and-query paradigm. We verify IoT-HiTrust's conver-gence, accuracy, and resiliency properties against self-promotion, discriminatory, bad-mouthing, ballot-stuffing, and opportunistic service attacks despite intermittent network disconnection to the cloud.