Recent Advances in Privacy Protection Technologies in Blockchain

With the continuous development and wide application of blockchain technology, the privacy leakage problem it faces is becoming more and more prominent, which must be paid great attention. Compared with the traditional centralized architecture, blockchain system does not specifically reply on a trusted central node to process and store data, avoiding the risk of single-point crash and data leakage of centralized servers. However, to achieve consensus among distributed nodes, all transaction records in the blockchain must be disclosed to all nodes, which will significantly increase the risk of privacy leakage. In this paper, we review the literatures published in recent years that discuss privacy issues related to blockchain technology, introduce the methodology and cryptographic measures currently applied, and summarize potential research trends in future.