博弈论在区块链中的应用研究  

Applications of Game Theory in Blockchain

作　　者：宋丽华[1] 李涛[1] 王伊蕾[1,2] SONG Li-Hua;LI Tao;WANG Yi-Lei(School of Information and Electrical Engineering,Ludong University,Yantai 264025,China;School of Information Science and Engineering,Qufu Normal University,Rizhao 276826,China)

机构地区：[1]鲁东大学信息与电气工程学院,烟台264025 [2]曲阜师范大学信息科学与工程学院,日照276826

出　　处：《密码学报》2019年第1期100-111,共12页Journal of Cryptologic Research

基　　金：国家自然科学基金(61502218)~~

摘　　要：区块链是比特币的底层技术,用于分布式地存储比特币的历史交易信息.区块链中的每个区块包含若干交易信息,矿工一旦挖到新的区块,就将其加入区块链,并以密码学方式保证区块信息不可篡改和不可伪造.为了保证系统正常运行,区块链将经济因素集成到激励层,为矿工提供充足的动机去寻找新的区块,激励层主要包括经济激励的发行机制和分配机制等.因此,如何设计高效实用的激励层成为区块链中的关键问题.博弈论作为现代数学的一个重要分支,已经成为分析经济学理论的标准工具之一,可以用来研究激励层的机制设计,提高区块链的效率和实用性.本文首先分析了博弈论、安全多方计算和比特币(区块链1.0)三者之间交叉的研究领域,其中包括理性安全多方计算,基于比特币的安全多方计算以及基于博弈论的比特币协议.然后将智能合约(区块链2.0)应用在可验证云计算中,使用博弈论为云计算中的委托人设计智能合约,该智能合约可以有效地防止云服务器合谋.最后在犯罪智能合约中引入随机参数,构造了Random-PublicLeaks,通过验证智能合约有效性,发现随机性的引入降低了犯罪智能合约的成功概率.As one of the underlying technics of Bitcoin, Blockchain is a distributed database recording the history of transactions. Each block includes several transactions and a new block is added to the Blockchain by miners. The data of transactions cannot be forged by utilizing cryptographic techniques. Economic factors are integrated into incentive level of Blockchain, which consist of issue and distribution of economic incentives to maintain normal operation of the system. Therefore, it is a crux in Blockchain to design efficient and practical incentive mechanisms. Game theory, as an important branch of modern mathematics, is one of standard tools to analyze economic theory, which can be utilized to solve such problems. This paper first takes a historic overview on game theory, secure multiparty computation and Bitcoin(Blockchain 1.0), including rational secure multi-party computation,secure multi-party computation based on Bitcoin and Bitcoin protocols based on game theory. Then the techniques of smart contracts(Blockchain 2.0) is used in verification of cloud computing, which can be collusion free. Finally, the construction of smart contract are highlighted: Random-PublicLeaks, a randomized criminal smart contract. It shows that the maximum probability of Random-PublicLeaks is rather low by introducing random parameters.

关 键 词：区块链 博弈论 比特币 智能合约 

分 类 号：TP311.13[自动化与计算机技术—计算机软件与理论] O225[自动化与计算机技术—计算机科学与技术]