关键词: 门限同态加密, 区块链, 交易, 隐私保护, 账户模型

Abstract: Blockchain is widely used because of its distributed processing, multiparty consensus, and immutable data. However, the open and transparent processing method will leak the privacy of users, and it is particularly important to use encryption technology to prevent the leakage of sensitive information. This paper proposes a privacy protection scheme for blockchain transactions based on threshold homomorphic encryption algorithm. Firstly, the confidentiality of sensitive transaction data is guaranteed by homomorphic encryption of the user’s account balance and transfer amount; Then, the corresponding transaction confirmation and transaction verification methods are designed. Finally, the security analysis and experimental verification of the proposed scheme are carried out, and the results show that the scheme has good stability and scalability, and is suitable for the general account model blockchain system.

Key words: threshold homomorphic encryption, blockchain, transaction, privacy protection, account model