区块链隐私保护和扩容关键技术研究

doi:10.19665/j.issn1001-2400.2020.05.005

摘要/Abstract

摘要：

区块链具有账本去中心化、数据不可篡改、信息公开透明等典型特征,在一定程度上解决了相互不信任的个体之间的协作与价值流转。但是,区块链的公开可验证性为用户隐私带来了安全挑战,同时其性能问题,特别是在交易吞吐量和可扩展性方面,也限制了区块链技术的进一步发展。从区块链的隐私保护和扩容技术两大方面进行了研究和探讨。首先,概述了区块链中的比特币技术和以太坊技术,以及相互之间的对比;然后,介绍了环签名、零知识证明、安全多方计算、同态承诺和子向量承诺等几种典型的面向区块链的隐私保护关键技术和发展现状,从链上、链下两个方面介绍了区块链扩容关键技术和案例分析。突破区块链发展中隐私保护和扩容两大瓶颈,使区块链具备智能合约功能,在保障用户隐私的前提下具有较高的交易吞吐量、可扩展性,满足金融、教育、社会管理、工业物流等广泛领域的实际需要,是区块链未来的发展方向。

关键词: 区块链, 智能合约, 去中心化, 隐私保护, 扩容

Abstract:

The blockchain has typical features such as decentralization of accounts, data irrevocability and transparency of information, which solves to a certain extent the collaboration and value flow between individuals who do not trust each other. However, the public verifiability of the blockchain poses security challenges for user privacy, while its performance issues, especially in terms of transaction throughput and scalability, also limit further development of blockchain technology. This paper researches and discusses the two major aspects of blockchain privacy protection and scaling technologies. First, it outlines the Bitcoin and ETH technologies in the blockchain and the comparison between them; then, it introduces several typical blockchain-oriented key technologies and development status of privacy protection such as ring signature, zero knowledge proof, secure multi-party computing, homomorphic commitment and subvector commitment. Similarly, the key technologies and case studies of blockchain scale-up are introduced from both up and down the chain to break through the two major bottlenecks in the development of blockchain privacy protection and scalability, so that the blockchain has a smart contract function, under the premise of protecting user privacy with high transaction throughput and scalability, to meet the actual needs of a wide range of fields such as finance, education, social management and industrial logistics, is the future direction of development of the blockchain.

Key words: blockchain, smart contracts, decentralization, privacy protection, scalability

中图分类号:

王慧,王励成,柏雪,刘清华,沈晓鹰. 区块链隐私保护和扩容关键技术研究[J]. 西安电子科技大学学报, 2020, 47(5): 28-39.

WANG Hui,WANG Licheng,BAI Xue,LIU Qinghua,SHEN Xiaoying. Research on key technology of blockchain privacy protection and scalability[J]. Journal of Xidian University, 2020, 47(5): 28-39.

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系统	账户模式	共识算法	交易验证	验证环境
比特币	基于交易	PoW	脚本语言	脚本引擎
以太坊	基于账户	PoW、PoS	智能合约	EVM

区块链系统	共识协议	扩容方式	隐私保护方式
比特币	PoW	侧链、闪电网络、PeerCensus、Byzcoin、ELASTICO
以太坊	PoW/PoS	Prism、Plasma、TrueBit、zk-Rollup、Piperine、zokrate	zk-SNARKs
Zerocash	PoW	侧链、闪电网络	zk-SNARKs、哈希承诺
Bitcoin-NG	PoW	一次生成多个区块
IOTA	PoW	DAG结构	IOTA信任模型
Algorand	PoS+BFT	混合共识协议
Omniledger	PoS+PBFT	分片
Rapidchain	PoS+BFT	分片
Monoxide	PoW	分片
Coda	PoS	零知识证明递归压缩	zk-SNARKs