Blockchain-based secure trusted clusters for multi-tiered Social IoT environments in edge-cloud networks

The rapid expansion of Social Internet of Things (SIoT) environments within edge-cloud networks necessitates robust mechanisms for secure communication and trust management. In response, this paper introduces a Blockchain-based secure Trusted Cluster (BTC) model that integrates blockchain technology with a comprehensive multi-tier trust evaluation framework. The proposed architecture delineates a three-layered approach: a data collection layer that initiates trust assessments based on data integrity and interaction metrics; an edge layer that employs router reliability and service path integrity to pre-process and securely route data; and a cloud layer that consolidates and immutably records trust scores via blockchain consensus mechanisms. By fusing direct trust–derived from time-decayed interaction and rating analyses–with indirect trust obtained through recommendations from credible nodes, the BTC model effectively mitigates a spectrum of security threats, including selective forwarding, data tampering, on-off behavior, good-bad mouth attacks. Extensive simulations leveraging real-world SIoT datasets demonstrate that the BTC model significantly enhances achieving up to 5 % improvement malicious node detection while reducing the computational cost of trust evaluations by as much as 6.8 %. These findings underscore the potential of blockchain-integrated trust frameworks to fortify the security, scalability, and reliability of SIoT networks in dynamic edge-cloud environments.