Short Paper: Design and Evaluation of Privacy-preserved Supply Chain System based on Public Blockchain
This addresses privacy concerns for supply chain stakeholders using public blockchains, but it is incremental as it builds on existing blockchain traceability systems.
The paper tackles the problem of privacy leakage in public blockchain-based supply chain systems by proposing a method that uses encryption and zero-knowledge proofs to conceal distribution information and addresses, while maintaining traceability. The implementation on Ethereum shows a cost of at most 2.6 USD per party in transaction fees.
Securing the traceability of products in the supply chain is an urgent issue. Recently, supply chain systems that use public blockchain (PBC) have been proposed. In these systems, PBC is used as a common database shared between supply chain parties to secure the integrity and reliability of distribution information such as ownership transfer records. Thus, these systems secure a high level of traceability in the supply chain. However, the distribution information, which can be private information, is made public since the information recorded in PBC can be read by anyone. In this paper, we propose a method for preserving privacy while securing traceability in a supply chain system using PBC. The proposed method preserves privacy by concealing the distribution information via encryption. In addition, the proposed method ensures distribution among legitimate supply chain parties while concealing their blockchain address by using a zero-knowledge proof to prove their authenticity. We implement the proposed method on Ethereum smart contracts and evaluate cost performance based on transaction fees. The results show that the fee per party is at most 2.6 USD.