Shangping Wang

Combining the supply chain with blockchain provides an immutable and publicly transparent ledger for the supply chain data history, addressing the issue of information asymmetry. Nevertheless, challenges still exist, including privacy leakage in data access and inefficiency in traceability, which hinders the application of blockchain in supply chains. To address these issues, we propose an adaptive access and tracking method for supply chain data based on sharding blockchain. Dividing the participating nodes into different shards enables independent and parallel verification and confirmation of transaction data, which enhances the efficiency and scalability of transaction processing in the supply chain ecosystem. In terms of the privacy level, the on-demand processing method for transaction data is leveraged, and the predicate encryption access control scheme with ciphertext commitment is constructed for the private data, which provides secure and adaptive access to sharding transaction data. Furthermore, a data tracking method is constructed with the trace source contract and Merkle tracking tree, which links upstream and downstream data in the supply chain, enabling the location of relevant tracking data and reducing the time required for data queries, achieving accurate supply chain traceability. The security analysis and experimental results demonstrate that the method is of flexibility and practicality.

The content-centric data sharing in Intelligent Transportation Systems (ITS) becomes increasingly imperative to improve road safety and traffic efficiency. In order to protect the privacy of vehicle users, data is generally encrypted prior to being shared, whereas it hinders data searching and utilization. Proxy re-encryption with equivalence test (PREET) has been proposed to test the equivalence between encrypted messages, and to delegate the decryption right of searched data to the specified user. However, existing PREET schemes primarily focus on the equivalence test between two ciphertexts, which aren’t suitable for the most practical scenarios that more than two ciphertexts need to be verified, due to the exposure of users’ extra information and the redundant computation. In this paper, to tackle these problems, we present a lightweight certificateless proxy re-encryption with multi-ciphertext equivalence test (CL-PREMET) for shared data to address the data search and authorized utilization over encrypted data in ITS. In our design, the users are allowed to efficiently and accurately search over massive encrypted data based on flexible multi-ciphertext analysis and to utilize their own keys rather than data owner’s key to decrypt the searched data after being authorized, without revealing any private and sensitive information. The CL-PREMET achieves the IND-CCA security and the OW-CCA security. Furthermore, the simulation experiment displays that the CL-PREMET is feasible. Compared with existing PREET schemes, in addition to being suitable for multi-ciphertext equivalence analysis, our scheme leverages the certificateless public key cryptography (CL-PKC) to avoid certificate management and key escrow problems.

The data collected by sensors in Internet of Things (IoT) plays a crucial role in achieving predictive analysis, resource optimization, and other related applications. However, it vulnerability to network attacks during transmission raises the issue of data authenticity, which hinders its utilization. Data authentication technology can be used to address this puzzle. Nevertheless, current solutions still need improvement in terms of security and efficiency. The centralized authentication schemes may suffer from single point of failure or center corruption. And existing decentralized solutions only achieved individual authentication, which is not efficient in distributed collection system. In this work, we present a new decentralized batch data authentication approach, named blockchain-assisted efficiency and secure data authentication scheme (BAESDA), to enable distributed authentication of multiple sensors’ data at once. BAESDA integrates a novel data authentication protocol and a smart contract based on homomorphic hash. The novel data authentication protocol based on hash chain is intended for sensors with limited computation, storage and communication to ensure the data authenticity and confidentiality, and enables the gateways to swiftly verify and aggregate the authentication messages. The data authentication contract is designed to efficiently achieve decentralized batch data authentication on the blockchain. Furthermore, the abnormal gateways can be identified by proposed abnormal data detection algorithm. Finally, we conduct a thorough security analysis for BAESDA, evaluate the proposed authentication protocol through simulation experiments, and deploy the proposed smart contracts on the Hyperledger Fabric 2.4.1 for testing. The results indicate that our solution is secure and efficient.