LPPAC: Lightweight privacy-preserving distributed payments with access control

The privacy-preserving distributed payment system leverages the advantages of its decentralized form while upholding data privacy. Currently, numerous solutions effectively safeguard users' privacy, encompassing transaction amounts and identities, but in practical deployments, these solutions may impose limitations due to their indiscriminate treatments. Recognizing that real-world transactions involve not only the exchange of funds but also the transfer of assets, we introduce a lightweight privacy-preserving distributed payment scheme called LPPAC, which differentiates its treatment of different levels of private data. The transformation of amounts, which directly involves monetary values, is rigorously protected using appropriate encryption techniques. Additionally, we incorporate transaction pruning techniques to reduce storage overhead and enhance operational efficiency. In the context of asset transfers, there maybe instances where parties other than the transacting entities need to be informed to make adequate preparations. However, the information related to asset transfers is inherently linked to transaction amounts. Therefore, we introduce an access control mechanism to allocate corresponding access rights. Through this approach, we theoretically establish that LPPAC can offer a precise privacy protection solution without compromising privacy. Furthermore, experimental results show the strong performance of LPPAC in practical applications.