A blockchain-based privacy protecting framework with multi-channel access control model for asset trading

With development of e-commerce and intelligent devices, large amounts of asset transaction data and traders’ identity information have been generated. It poses huge challenges to the data security and privacy when data are stored in a centralized trading system. Here, considering the need of data sharing and data privacy in asset trading, we proposed a blockchain-based privacy protecting framework to accommodate both aspects of these requirements. The proposed framework combines a multi-channel access control model and smart contracts to enhance the security and transparency of asset trading within permissioned channels while maintaining privacy for transactions occurring outside of these channels. Furthermore, regarding market efficiency and transaction fairness, we design trading algorithm of double auction to make transaction more automated and intelligent. Finally, we implement asset trading prototype based on Hyperledger Fabric and evaluate the performance of model. The experimental results show that the proposed multi-channel blockchain-based framework realized intra-channel date sharing and extra-channel privacy protection. Our framework achieves enhanced security, high efficiency and strong traceability for assert trading.