Space-efficient logging for Supply Chain Traceability based on blockchain

Supply chain traceability has become a prime requirement for industries to ensure product quality. Existing solutions often rely on trusted third parties to track the provenance and journey of products in a centralized manner. Blockchain provides a decentralized solution that can achieve immutability and auditability for digital records of supply chain transactions without the need of third parties. However, existing blockchainbased methods do not carefully consider the tracing process, which often needs to retrieve transaction logs related to the target product from a large number of irrelevant logs, resulting in unsatisfactory space overhead and slow query time. Moreover, current smart contracts often ignore the time spent on Ethereum calls, which consume a lot of time when fetching logs. In this paper, we propose a space-saving blockchain-based mechanism to efficiently explore the transaction logs for supply chain traceability. The mechanism introduces a new filter to identify relevant logs fast while using little space, and we propose a new token that extends the data structure in existing smart contracts, reducing the number of Ethereum calls. The experimental results show that our scheme achieves 49% improvement on space consumption and 400ms speed-up in time consumption compared with the state-of-art methods.