Consortium Blockchain Based Lightweight Message Authentication and Auditing in Smart Home

Currently, smart homes rely heavily on wireless sensor networks (WSNs), which typically consist of wireless sensor nodes with limited resources and are scattered throughout the network. This topology makes them vulnerable to packet sniffing, spoofing, and other malicious attacks, which can result in the leakage of private data collected by devices. Additionally, managing the device key for the entire system becomes difficult as more devices are added. Moreover, the centralization of current cloud service management in smart home systems poses a serious single-point-of-failure problem, and the private data of cloud outsourcing cannot receive strict privacy supervision, ultimately relying entirely on the trust of enterprises. To address these issues, this paper proposes using a consortium blockchain and InterPlanetary File System (IPFS) instead of the existing centralized structure. An improved pairing-free certificateless aggregated signature(CLAS) scheme ensures the security of message authentication and solves the device key management problem. Our scheme reduces the computational and communication overheads at the device side by 50% and 25%, respectively, compared with existing schemes in WSNs. The overall computational overhead is also reduced by 28.6%, making it more suitable for smart home scenarios. Additionally, we use an auditing method based on Merkle root hash verification to ensure the reliability of data storage in IPFS.