TruChord: A Secure Communication Framework for Hybrid SDIoT Architecture Based on Chord Overlay

As a highly integrated and comprehensive application of the new generation of information technology, IoT inevitably comes with security issues. The communication security of IoT devices is the foundation for their large-scale development. To address the problems of missing cross-domain identity authentication, low routing efficiency, and frequent malicious attacks in hybrid SDIoT, we propose a secure and trusted communication framework for IoT based on overlay networks, namely TruChord. This framework introduces DICE technology to generate device firmware identifiers, constructs a trust chain, and realizes hardware binding of device identities and firmware integrity measurement. Meanwhile, it designs a domain-specific identifier mapping mechanism, which integrates SDN domain DPID, IP domain prefix, and firmware identifiers to make physically adjacent nodes logically adjacent on the ring. Finally, it proposes a hierarchical trust aggregation protocol, which ensures secure communication between nodes through intra-domain local verification and cross-domain global aggregation with the help of a trust mechanism. Through formal proof, TruChord can resist Sybil attacks and collusion attacks. Simulation experiments show that TruChord outperforms the comparison frameworks in core indicators such as end-to-end delay, network traffic, and convergence time, providing an efficient solution for cross-domain secure communication of IoT devices.