Blockchain assisted public audit with cross-authentication for shared data in Ad Hoc networks

The dynamic nature of Ad Hoc networks improves the overall efficiency of the network by providing flexibility and adaptability, while also posing challenges to the data security of shared users. Considering the privacy and integrity requirements of shared data, researchers have developed various public audits to prevent malicious storage servers from compromising data privacy and integrity during sharing. However, considering the competition, benefit, cost, and confidentiality, a potential fraudulent data owner in Ad Hoc networks may share inconsistent or incomplete data that differs from its claims. Additionally, a fraudulent owner may manipulate the validation results, making the server liable for data corruption. Thus far, the problem of a fraudulent data owner in public audit for shared data is unsolved. To address this challenge, we present a blockchain-assisted public audit with cross-authentication for shared data in Ad Hoc networks, using an iterative hash chain structure to ensure a continuous, seamless flow of united authentication among parties over time. Our scheme resists fraudulent owners, allows data users to audit shared data in a semi-non-interactive mode to reduce communication costs, and achieves decentralization by adopting blockchain rather than a third-party auditor (TPA) to prevent data disclosure. Moreover, it supports multiple public audits to maintain a sustainable integrity of the data, and allows users to audit shared data even in highly privacy-protective contexts where the owner’s identity is anonymized. Security proof and extensive experiments are conducted to demonstrate the advantages of our scheme.