With the rapid development of Internet of Things (IoT) devices, the volume of data generate across various fields, such as smart healthcare, smart home, smart transportation has significantly increased. This surge raises serious concerns about the secure storage of sensitive data for e.g., biometric information (e.g., fingerprints and facial recognition) and medical records etc. The centralized cloud computing paradigm provides various cost-effective services to IoT applications users. Despite of various benefits of centralized cloud, it fails to adequately meet the strict latency and security requirement of various IoT applications. Fog computing is proposed to enhance the real-time data processing for various latency sensitive IoT applications by extending the cloud computing services closer to the data sources. In this paper we proposed a novel blockchain based distributed fog computing model that ensures secure distributed storage for various IoT data. The blockchain network acts a trusted third party aimed at establishing secure communication among IoT devices and fog node within the fog layer. It details a distinctive Elliptic Curve Diffie–Hellman (ECDH) protocol for reliable and secure data storage and retrieval based on requests and responses from heterogeneous IoT devices. Additionally, a Merkle tree-based data structure is used to verify data integrity, ensuring secure and tamper-proof data management within the blockchain-enabled fog computing framework. It provides a formal security proof using AVISPA tools for the proposed scheme, ensuring that it meets the necessary security standards and can be trusted for protecting sensitive IoT data. Finally, the proposed scheme is compared with existing security schemes, such as AES, ABE, RSA, and Hybrid RSA in terms of resource utilization, computational cost, communication cost and execution cost. The experimental results exemplify that the proposed scheme outperform other state of the art schemes.

中文翻译：

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一种面向物联网应用的安全分布式存储系统的区块链辅助雾计算


随着物联网 （IoT） 设备的快速发展，智能医疗、智能家居、智能交通等各个领域产生的数据量显著增加。这种激增引发了人们对敏感数据安全存储的严重担忧，例如生物识别信息（例如指纹和面部识别）和医疗记录等。集中式云计算范式为 IoT 应用程序用户提供各种经济高效的服务。尽管集中式云具有多种优势，但它无法充分满足各种 IoT 应用程序严格的延迟和安全要求。雾计算旨在通过将云计算服务扩展到更靠近数据源的位置来增强各种延迟敏感型 IoT 应用的实时数据处理。在本文中，我们提出了一种基于区块链的新型分布式雾计算模型，可确保各种物联网数据的安全分布式存储。区块链网络充当受信任的第三方，旨在在 IoT 设备和雾层内的雾节点之间建立安全通信。它详细介绍了一种独特的椭圆曲线 Diffie-Hellman （ECDH） 协议，用于根据异构 IoT 设备的请求和响应进行可靠和安全的数据存储和检索。此外，基于 Merkle 树的数据结构用于验证数据完整性，确保在支持区块链的雾计算框架内实现安全且防篡改的数据管理。它使用 AVISPA 工具为拟议的方案提供正式的安全证明，确保其符合必要的安全标准，并且可以信任地保护敏感的 IoT 数据。 最后，将所提方案与现有的安全方案（如 AES、ABE、RSA 和 Hybrid RSA）在资源利用率、计算成本、通信成本和执行成本方面进行了比较。实验结果表明，所提出的方案优于其他最先进的方案。