Secure and trusted sharing mechanism of private data for Internet of Things

In recent years, the rapid development of Internet of Things (IoT) technology has led to a significant increase in the amount of data stored in the cloud. However, traditional IoT systems rely primarily on cloud data centers for information storage and user access control services. This practice creates the risk of privacy breaches on IoT data sharing platforms, including issues such as data tampering and data breaches. To address these concerns, blockchain technology, with its inherent properties such as tamper-proof and decentralization, has emerged as a promising solution that enables trusted sharing of IoT data. Still, there are challenges to implementing encrypted data search in this context. This paper proposes a novel searchable attribute cryptographic access control mechanism that facilitates trusted cloud data sharing. Users can use keywords To efficiently search for specific data and decrypt content keys when their properties are consistent with access policies. In this way, cloud service providers will not be able to access any data privacy-related information, ensuring the security and trustworthiness of data sharing, as well as the protection of user data privacy. Our simulation results show that our approach outperforms existing studies in terms of time overhead. Compared to traditional access control schemes,our approach reduces data encryption time by 33%, decryption time by 5%, and search time by 75%. • Blockchain facilitates data sharing by offloading computation to the chain, encrypting cloud-stored data, and safeguarding keywords onchain. • Smart contracts allow keyword searches for on-chain/off-chain collaboration. It also enables IoT attribute-based encrypted data search, preserving user and data privacy, accelerating searches, and securing data/confidential access. Encrypted owner keys prevent unauthorized viewing. • Blockchain’s keyword storage frees searches from untrusted entities. • Simulations show improved efficiency in encryption, decryption, and search times over current methods.