区块链安全问题:研究现状与展望

韩璇; 袁勇; 王飞跃

doi:10.16383/j.aas.c180710

区块链安全问题:研究现状与展望

doi: 10.16383/j.aas.c180710

韩璇^1,2,,
袁勇^1,2, ,,
王飞跃^1,3,4,

1.
中国科学院自动化研究所复杂系统管理与控制国家重点实验室北京 100190
2.
青岛智能产业技术研究院平行区块链技术创新中心青岛 266109
3.
国防科学技术大学军事计算实验与平行系统技术中心长沙 410073
4.
中国科学院大学中国经济与社会安全研究中心北京 101408

基金项目:

国家自然科学基金 71702182

国家自然科学基金 71472174

国家自然科学基金 61233001

国家自然科学基金 61533019

国家自然科学基金 71232006

详细信息

作者简介:
韩璇中国科学院自动化研究所复杂系统管理与控制国家重点实验室助理工程师.2018年获得中国科学院大学软件工程硕士学位.主要研究方向为理论密码与区块链技术.E-mail:xuan.han@ia.ac.cn

王飞跃中国科学院自动化研究所复杂系统管理与控制国家重点实验室主任, 国防科技大学军事计算实验与平行系统技术研究中心主任, 中国科学院大学中国经济与社会安全研究中心主任, 青岛智能产业技术研究院院长.主要研究方向为平行系统的方法与应用, 社会计算, 平行智能以及知识自动化.E-mail:feiyue.wang@ia.ac.cn

通讯作者:
袁勇中国科学院自动化研究所复杂系统管理与控制国家重点实验室副研究员.青岛智能产业技术研究院副院长.2008年获得山东科技大学计算机软件与理论专业博士学位.主要研究方向为社会计算, 计算广告学, 区块链技术.本文通信作者.E-mail:yong.yuan@ia.ac.cn

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出版历程
- 收稿日期: 2018-10-31
- 录用日期: 2018-01-14
- 刊出日期: 2019-01-20

Security Problems on Blockchain: The State of the Art and Future Trends

HAN Xuan^{1,2
,},
YUAN Yong^{1,2
, ,},
WANG Fei-Yue^{1,3,4
,}

1.
The State Key Laboratory for Management and Control of Complex Systems, Institute of Automation, Chinese Academy of Sciences, Beijing 100190
2.
Innovation Center for Parallel Blockchain, Qingdao Academy of Intelligent Industries, Qingdao 266109
3.
Research Center of Military Computational Experiments and Parallel Systems, National University of Defense Technology, Changsha 410073
4.
Center of China Economic and Social Security, The University of Chinese Academy of Sciences, Beijing 101408

Funds:

National Natural Science Foundation of China 71702182

National Natural Science Foundation of China 71472174

National Natural Science Foundation of China 61233001

National Natural Science Foundation of China 61533019

National Natural Science Foundation of China 71232006

More Information

Author Bio:
Assistant engineer at the State Key Laboratory for Management and Control of Complex Systems, Institute of Automation, Chinese Academy of Sciences. She received her master degree in software engineering from University of Chinese Academy of Sciences in 2018. Her research interest covers theory of cryptography and blockchain technology

State specially appointed expert and director of the State Key Laboratory for Management and Control of Complex Systems, Institute of Automation, Chinese Academy of Sciences. Professor of the Research Center for Computational Experiments and Parallel Systems Technology, National University of Defense Technology. Director of China Economic and Social Security Research Center in University of Chinese Academy of Sciences. Dean of Qingdao Academy of Intelligent Industries. His research interest covers methods and applications for parallel systems, social computing, parallel intelligence, and knowledge automation

Corresponding author: YUAN Yong Associate professor at the State Key Laboratory for Management and Control of Complex Systems, Institute of Automation, Chinese Academy of Sciences. He is also the vice president of Qingdao Academy of Intelligent Industries. He received his Ph. D. degree of computer software and theory from Shandong University of Science and Technology in 2008. His research interest covers social computing, computational advertising, and blockchain. Corresponding author of this paper

摘要

摘要: 区块链是比特币底层的核心技术，展示了在自组织模式下实现大规模协作的巨大潜力，为解决分布式网络中的一致性问题提供了全新的方法.随着比特币的广泛流通和去中心化区块链平台的蓬勃发展，区块链应用也逐渐延伸至金融、物联网等领域，全球掀起了区块链的研究热潮.然而，区块链为无信任的网络环境提供安全保障的同时，也面临安全和隐私方面的严峻挑战.本文定义了区块链系统设计追求的安全目标，从机制漏洞、攻击手段和安全措施三方面对区块链各层级的安全问题进行全面分析，提出了区块链的平行安全概念框架，并总结未来区块链安全问题的研究重点.本文致力于为区块链研究提供有益的安全技术理论支撑与借鉴.
- 区块链 /
- 可证明安全 /
- 隐私保护 /
- 安全威胁 /
- 监管
Abstract: As the core underlying technology of Bitcoin, blockchain shows the potential of achieving large-scale self-organizing, and provides a new approach to solve the consistency problem in P2P networks. With the widespread circulation of Bitcoin and the rapid development of decentralized blockchain platforms, blockchain has been gradually applied to many fields such as finance and Internet of Things, and related studies have been blooming across the world. Blockchain provides a security architecture in the trustless network environment, however, it also faces serious challenges in security and privacy. In this paper, we defined the security objectives and gave a comprehensive analysis of blockchain security from the aspects of the existing vulnerabilities, attacks and security measures. In addition, we proposed a conceptual framework of parallel security and summarized the key directions of future security research on blockchain. This paper is devoted to providing useful theoretical support and reference for future blockchain researches.
- Blockchain /
- provable security /
- privacy protection /
- security threat /
- supervision
注释:

1) 本文责任编委魏庆来

HTML全文

图 1 比特币区块链结构

Fig. 1 Structure of bitcoin blockchain

下载: 全尺寸图片幻灯片

图 2 区块链安全目标

Fig. 2 Security objectives on blockchain

下载: 全尺寸图片幻灯片

图 3 区块链体系架构

Fig. 3 The basic framework of blockchain

下载: 全尺寸图片幻灯片

图 4 区块链的安全问题

Fig. 4 Security threats on blockchain

下载: 全尺寸图片幻灯片

图 5 区块链的平行安全框架

Fig. 5 A framework of parallel security on blockchain

下载: 全尺寸图片幻灯片

表 1 量子计算对一般密码算法的影响^[27]

Table 1 Impact of quantum computing on common cryptographic algorithms ^[27]

密码算法	类型	功能	安全性影响
AES	对称密码	加密	攻击难度减半
SHA-2, SHA-3	-	哈希函数	攻击难度减半
RSA	公钥密码	加密	攻破
ECDSA, ECDH	公钥密码	签名, 密钥交换	攻破
DSA	公钥密码	签名, 密钥交换	攻破

下载: 导出CSV

参考文献(75)

[1]	Nakamoto S. Bitcoin: a peer-to-peer electronic cash system[Online], available: https://bitcoin.org/bitcoin.pdf, October 5, 2018
[2]	Dwork C, Naor M. Pricing via processing or combatting junk mail. In: Proceedings of the 12th Annual International Cryptology Conference. California, USA: CRYPTO, 1992. 139-147
[3]	袁勇, 王飞跃.区块链技术发展现状与展望.自动化学报, 2016, 42(4):481-494 http://www.aas.net.cn/CN/abstract/abstract18837.shtml Yuan Yong, Wang Fei-Yue. Blockchain:the state of the art and future trends. Acta Automatica Sinica, 2016, 42(4):481-494 http://www.aas.net.cn/CN/abstract/abstract18837.shtml
[4]	Walport M. Distributed ledger technology: beyond blockchain[Online], available: https://www.gov.uk/government/news/distributed-ledger-technology-beyond-block-chain, October 5, 2018
[5]	Ministry of Industry and Information Technology. Chinese blockchain technology and application development white paper2016[Online], available: http://www.fullrich.com/Uploads/article/file/2016/1020/580866e374069.pdf, October 5, 2018
[6]	McWaters R, Bruno G, Galaski R, Chaterjee S. The future of financial infrastructure: an ambitious look at how blockchain can reshape financial services[Online], available: https://www.weforum.org/reports/the-futureof-financialinfrastructure-an-ambitious-look-at-how-blockchain-can-reshape-financial-services, October 5, 2018
[7]	Takemoto Y, Knight S. Mt. Gox files for bankruptcy, hit with lawsuit[Online]. available: http://www.reuters.com/article/us-bitcoin-mtgox-bankruptcy-idUSBREA1R0FX20140228, October 5, 2018
[8]	Hon M T W K, Palfreyman J, Tegart M. Distributed ledger technology & Cybersecurity[Online]. available: https://ec.europa.eu/futurium/en/content/distributed-ledger-technology-cybersecurity, October 5, 2018
[9]	Yaga D, Mell P, Roby N, Scarfone K. Blockchain technology overview[Online]. available: https://csrc.nist.gov/publications/detail/nistir/8202/draft, October 5, 2018
[10]	De Prisco R, Lampson B, Lynch N. Revisiting the Paxos algorithm. In: Proceedings of the 11th International Workshop on Distributed Algorithms. Saarbrücken, Germany: Springer 1997. 111-125.
[11]	Lamport L. The part-time parliament. ACM Transactions on Computer Systems, 1998, 16(2):133-169 doi: 10.1145/279227.279229
[12]	Castro M, Liskov B. Practical Byzantine fault tolerance. In: Proceedings of the 3rd Symposium on Operating Systems Design and Implementation. New Orleans, USA: OSDI, 1999. 173-86
[13]	Ongaro D, Ousterhout J K. In search of an understandable consensus algorithm. In: Proceedings of the USENIX Annual Technical Conference. Philadelphia, PA, USA: USENIX ATC, 2014. 305-119
[14]	Oki B M, Liskov B H. Viewstamped replication: a new primary copy method to support highly-available distributed systems In: Proceedings of the 7th Annual ACM Symposium on Principles of Distributed Computing. Toronto, Ontario, Canada: ACM, 1988. 8-17
[15]	King S, Nadal S. Ppcoin: peer-to-peer crypto-currency with proof-of-stake[Online], available: https://bitcoin.org/bitcoin.pdf, October 5, 2018
[16]	Buterin V. A next-generation smart contract and decentralized application platform[Online], available: https://github.com/ethereum/wiki/wiki/White-Paper, October 5, 2018
[17]	Yuan Yong, Wang Fei-Yue. Blockchain and cryptocurrencies:model, techniques, and applications. IEEE Transactions on Systems, Man, and Cybernetics:Systems, 2018, 48(9):1421-1428 doi: 10.1109/TSMC.2018.2854904
[18]	Peters G W, Panayi E. Understanding modern banking ledgers through blockchain technologies: future of transaction processing and smart contracts on the internet of money. Banking Beyond Banks and Money. Berilin: Springer, 2016. 239-278
[19]	VukolićM. Rethinking permissioned blockchains. In: Proceedings of the ACM Workshop on Blockchain, Cryptocurrencies and Contracts. Abu Dhabi, United Arab Emirates: ACM, 2017. 3-7
[20]	Danezis G, Meiklejohn S. Centrally banked cryptocurrencies[Online]. available: https://arxiv.org/abs/1505.06895, October 5, 2018
[21]	Halpin H, Piekarska M. Introduction to security and privacy on the blockchain. In: Proceedings of the 2017 Security and Privacy Workshops (EuroS&PW). Paris, France: IEEE, 2017. 1-3
[22]	Heilman E, Kendler A, Zohar A, Goldberg S. Eclipse attacks on bitcoin's peer-to-peer network. In: Proceedings of 24th USENIX Security Symposium. Washington, D.C, USA: USENIX, 2015: 129-144
[23]	Delmolino K, Arnett M, Kosba A, Miller A, Shi E. Step by step towards creating a safe smart contract: lessons and insights from a cryptocurrency lab. In: Proceedings of the International Conference on Financial Cryptography and Data Security. Christ Church, Barbados: Springer, 2016. 79-94
[24]	Bernstein D J. Introduction to Post-quantum Cryptography. Berlin:Springer-Verlag, 2009. 1-14
[25]	秦波, 陈李昌豪, 伍前红, 张一锋, 钟林, 郑海彬.比特币与法定数字货币.密码学报, 2017, 4(2):176-186 http://d.old.wanfangdata.com.cn/Periodical/mmxb201702008 Qin Bo, Chen Li Chang-Hao, Wu Qian-Hong, Zhang Yi-Feng, Zhong Lin, Zheng Hai-Bin. Bitcoin and digital fiat currency. Journal of Cryptologic Research, 2017, 4(2):176-186 http://d.old.wanfangdata.com.cn/Periodical/mmxb201702008
[26]	Garay J, Kiayias A, Leonardos N. The bitcoin backbone protocol: analysis and applications. In: Proceedings of the 34th Annual International Conference on the Theory and Applications of Cryptographic Techniques. Sofia, Bulgaria: EUROCRYPT, 2015. 281-310
[27]	Chen L, Jordan S, Liu Y K, Moody D, Peralta R C, Perlner R A. Report on post-quantum cryptography[Online], available: https://www.nist.gov/publications/report-post-quantum-cryptography, October 5, 2018
[28]	Torres W A A, Steinfeld R, Sakzad A, Liu J K, Kuchta V, Bhattacharjee N, et al. Post-quantum one-time linkable ring signature and application to ring confidential transactions in blockchain (lattice ringCT v1. 0). In: Proceedings of the 23rd Australasian Conference on Information Security and Privacy. Wollongong, NSW, Australia: ACISP, 2018. 558-576
[29]	Jarecki S, Kiayias A, Krawczyk H, Xu J. Highly-efficient and composable password-protected secret sharing (or: how to protect your bitcoin wallet online). In: Proceedings of 2016 IEEE European Symposium on Security and Privacy (EuroS&P). Saarbrucken, Germany: IEEE, 2016. 276-291
[30]	Fleder M, Kester M S, Pillai S. Bitcoin transaction graph analysis[Online]. available: https://arxiv.org/abs/1502.01657, October 5, 2018
[31]	Saberhagen N. CryptoNote v 2.0[Online]. available: https://static.coinpaprika.com/storage/cdn/whitepapers/1611.pdf, October 5, 2018
[32]	Noether S. Ring signature confidential transactions for Monero[Online]. available: https://eprint.iacr.org/2015/1098, October 5, 2018
[33]	Miers I, Garman C, Green M, Rubin A D. Zerocoin: anonymous distributed e-cash from bitcoin. In: Proceedings of the 2013 IEEE Symposium on Security and Privacy. Berkeley, CA, USA: IEEE, 2013. 397-411
[34]	Bitansky N, Chiesa A, Ishai Y, Paneth O, Ostrovsky R. Succinct non-interactive arguments via linear interactive proofs. In: Proceedings of the 2013 Theory of Cryptography. Tokyo, Japan: Springer, 2013. 315-333
[35]	Sasson E B, Chiesa A, Garman C, Green M, Miers I, Tromer E, et al. Zerocash: decentralized anonymous payments from bitcoin. In: Proceedings of the 2014 IEEE Symposium on Security and Privacy. CA, USA: IEEE, 2014. 459-474
[36]	Decker C, Wattenhofer R. Bitcoin transaction malleability and MtGox. In: Proceedings of the 2014 European Symposium on Research in Computer Security. Wroclaw, Poland: ESORICS, 2014. 313-326
[37]	Karame G O, Androulaki E, Roeschlin M, Gervais A, Ĉapkun S. Misbehavior in bitcoin: a study of double-spending and accountability. ACM Transactions on Information and System Security (TISSEC), 2015, 18(1): No.2
[38]	Rajput U, Abbas F, Heekuck O. A solution towards eliminating transaction malleability in bitcoin. Journal of Information Processing Systems, 2018, 14(4):837-850
[39]	Lewenberg Y, Bachrach Y, Sompolinsky Y, Zohar A, Rosenschein J S. Bitcoin mining pools: a cooperative game theoretic analysis. In: Proceedings of the 2015 International Conference on Autonomous Agents and Multiagent Systems. Istanbul, Turkey: AAMAS, 2015. 919-927
[40]	Nayak K, Kumar S, Miller A, Shi E. Stubborn mining: generalizing selfish mining and combining with an eclipse attack. In: Proceedings of the 2016 IEEE European Symposium on Security and Privacy (EuroS&P). Saarbrucken, Germany: IEEE, 2016. 305-320
[41]	Reed M G, Syverson P F, Goldschlag D M. Anonymous connections and onion routing. IEEE Journal on Selected areas in Communications, 1998, 16(4):482-494 doi: 10.1109/49.668972
[42]	Bonneau J, Narayanan A, Miller A, Clark J, Kroll J A, Felten E W. Mixcoin: anonymity for bitcoin with accountable mixes. In: Proceedings of the 2014 International Conference on Financial Cryptography and Data Security. Christ Church, Barbados: Springer, 2014. 486-504
[43]	Valenta L, Rowan B. Blindcoin: blinded, accountable mixes for bitcoin. In: Proceedings of the 2015 International Conference on Financial Cryptography and Data Security. San Juan, Puerto Rico: Springer, 2015. 112-126
[44]	Maxwell G. CoinJoin: bitcoin privacy for the real world[Online]. available: https://bitcointalk.org/index.php, October 5, 2018
[45]	Ruffing T, Moreno-Sanchez P, Kate A. CoinShuffle: practical decentralized coin mixing for bitcoin. In: Proceedings of the 2014 European Symposium on Research in Computer Security. Wroclaw, Poland: ESORICS, 2014. 345-364
[46]	Ziegeldorf J H, Grossmann F, Henze M, Inden N, Wehrle K. Coinparty: secure multi-party mixing of bitcoins. In: Proceedings of the 5th ACM Conference on Data and Application Security and Privacy. New York, USA: ACM, 2015. 75-86
[47]	袁勇, 倪晓春, 曾帅, 王飞跃.区块链共识算法的发展现状与展望.自动化学报, 2018, 44(11):2011-2022 http://www.aas.net.cn/CN/abstract/abstract19383.shtml Yuan Yong, Ni Xiao-Chun, Zeng Shuai, Wang Fei-Yue. Blockchain consensus algorithms:the state of the art and future trends. Acta Automatica Sinica, 2018, 44(11):2011-2022 http://www.aas.net.cn/CN/abstract/abstract19383.shtml
[48]	Kiayias A, Panagiotakos G. Speed-security tradeoffs in blockchain protocols[Online]. available: https://eprint.iacr.org/2015/1019.pdf, October 5, 2018
[49]	Sompolinsky Y, Zohar A. Secure high-rate transaction processing in bitcoin. In: Proceedings of the 2015 International Conference on Financial Cryptography and Data Security. San Juan, Puerto Rico: Springer, 2015. 507-527
[50]	Pass R, Seeman L, Shelat A. Analysis of the blockchain protocol in asynchronous networks. In: Proceedings of the 2017 Annual International Conference on the Theory and Applications of Cryptographic Techniques. Paris, France: EUROCRYPT, 2017. 643-673
[51]	Kiayias A, Russell A, David B, Oliynykov R. Ouroboros: a provably secure proof-of-stake blockchain protocol. In: Proceedings of the 2017 Annual International Cryptology Conference. Santa Barbara, USA: CRYPTO, 2017. 357-388
[52]	Bentov I, Lee C, Mizrahi A, Rosenfeld M. Proof of activity:extending bitcoin's proof of work via proof of stake[extended abstract]. ACM SIGMETRICS Performance Evaluation Review, 2014, 42(3):34-37 doi: 10.1145/2695533
[53]	Duong T, Fan L, Zhou H S. 2-hop blockchain: combining proof-of-work and proof-of-stake securely[Online]. available: https://eprint.iacr.org/2016/716.pdf, October 5, 2018
[54]	Gilad Y, Hemo R, Micali S, Vlachos G, Zeldovich N. Algorand: scaling byzantine agreements for cryptocurrencies. In: Proceedings of the 26th Symposium on Operating Systems Principles. Shanghai, China: ACM, 2017. 51-68
[55]	Chen L, Xu L, Shah N, Gao Z, Lu Y, Shi W. On security analysis of proof-of-elapsed-time (poet). In: Proceedings of the 2017 International Symposium on Stabilization, Safety, and Security of Distributed Systems. MA, USA: Springer, Cham, 2017. 282-297
[56]	Milutinovic M, He W, Wu H, Kanwal M. Proof of luck: an efficient blockchain consensus protocol[Online], available: https://eprint.iacr.org/2017/249.pdf, October 5, 2018
[57]	曾帅, 袁勇, 倪晓春, 王飞跃.面向比特币的区块链扩容:关键技术, 制约因素与衍生问题.自动化学报, DOI: 10.16383/j.aas.c180100 Zeng Shuai, Yuan Yong, Ni Xiao-Chun, Wang Fei-Yue. Scaling blockchain towards bitcoin:key technologies, constraints and related issues. Acta Automatica Sinica, DOI: 10.16383/j.aas.c180100
[58]	Luu L, Narayanan V, Zheng C, Baweja K, Gilbert S, Saxena P. A secure sharding protocol for open blockchains. In: Proceedings of the 2016 ACM SIGSAC Conference on Computer and Communications Security. New York, USA: ACM, 2016. 17-30
[59]	Kokoris-Kogias E, Jovanovic P, Gasser L, Gailly N, Ford B. Omniledger: a secure, scale-out, decentralized ledger via sharding. In: Proceedings of the 2018 IEEE Symposium on Security and Privacy (SP). CA, USA: IEEE, 2018. 583-598
[60]	Eyal I, Sirer E G. Majority is not enough:Bitcoin mining is vulnerable. Communications of the ACM, 2018, 61(7):95-102 doi: 10.1145/3234519
[61]	Bag S, Ruj S, Sakurai K. Bitcoin block withholding attack:analysis and mitigation. IEEE Transactions on Information Forensics and Security, 2017, 12(8):1967-1978 doi: 10.1109/TIFS.2016.2623588
[62]	Kiayias A, Koutsoupias E, Kyropoulou M, Tselekounis Y. Blockchain mining games. In: Proceedings of the 2016 ACM Conference on Economics and Computation. Maastricht, The Netherlands: ACM, 2016. 365-382
[63]	Carlsten M, Kalodner H, Weinberg S M, Narayanan A. On the instability of bitcoin without the block reward. In: Proceedings of the 2016 ACM SIGSAC Conference on Computer and Communications Security. Vienna, Austria: ACM, 2016. 154-167
[64]	Luu L, Chu D H, Olickel H, Saxena P, Hobor A. Making smart contracts smarter. In: Proceedings of the 2016 ACM SIGSAC Conference on Computer and Communications Security. Vienna, Austria: ACM, 2016: 254-269
[65]	Atzei N, Bartoletti M, Cimoli T. A survey of attacks on ethereum smart contracts (sok). In: Proceedings of the 2017 International Conference on Principles of Security and Trust. Uppsala, Sweden: Springer, 2017. 164-186
[66]	Zhang F, Cecchetti E, Croman K, Juels A, Shi E. Town crier: an authenticated data feed for smart contracts. In: Proceedings of the 2016 ACM SIGSAC conference on computer and communications security. Vienna, Austria: ACM, 2016. 270-282
[67]	Peterson J, Krug J, Zoltu M, Williams A K, Alexander S. Augur: a decentralized oracle and prediction market platform[Online]. available: http://media.abnnewswire.net/media/en/whitepaper/rpt/93144-Augur_Whitepaper.pdf, October 5, 2018
[68]	Grishchenko I, Maffei M, Schneidewind C. A semantic framework for the security analysis of ethereum smart contracts. In: Proceedings of the 2018 International Conference on Principles of Security and Trust. Thessaloniki, Greece: Springer, 2018. 243-269
[69]	Kosba A, Miller A, Shi E, Wen Z, Papamanthou C. Hawk: The blockchain model of cryptography and privacy-preserving smart contracts. In: Proceedings of the 2016 IEEE Symposium on Security and Privacy (SP). CA, USA: IEEE, 2016. 839-858
[70]	袁勇, 周涛, 周傲英, 段永朝, 王飞跃.区块链技术:从数据智能到知识自动化.自动化学报, 2017, 43(9):1485-1490 http://www.aas.net.cn/CN/abstract/abstract19125.shtml Yuan Yong, Zhou Tao, Zhou Ao-Ying, Duan Yong-Chao, Wang Fei-Yue. Blockchain technology:from data intelligence to knowledge automation. Acta Automatica Sinica, 2017, 43(9):1485-1490 http://www.aas.net.cn/CN/abstract/abstract19125.shtml
[71]	袁勇, 王飞跃.平行区块链:概念, 方法与内涵解析.自动化学报, 2017, 43(10):1703-1712 http://d.old.wanfangdata.com.cn/Periodical/zdhxb201710003 Yuan Yong, Wang Fei-Yue. Parallel blockchain:concept, methods and issues. Acta Automatica Sinica, 2017, 43(10):1703-1712 http://d.old.wanfangdata.com.cn/Periodical/zdhxb201710003
[72]	Thomas S, Schwartz E. A protocol for interledger payments[Online]. available: https: //interledger.org/interledger. pdf, October 5, 2018
[73]	Collberg C, Davidson J, Giacobazzi R, Gu Y X. Toward digital asset protection. IEEE Intelligent Systems, 2011, 26(6):8-13 doi: 10.1109/MIS.2011.106
[74]	王飞跃.计算实验方法与复杂系统行为分析和决策评估.系统仿真学报, 2004, 16(5):893-897 doi: 10.3969/j.issn.1004-731X.2004.05.009 Wang Fei-Yue. Computational experiments for behavior analysis and decision evaluation of complex systems. Journal of System Simulation, 2004, 16(5):893-897 doi: 10.3969/j.issn.1004-731X.2004.05.009
[75]	王飞跃.人工社会、计算实验、平行系统:关于复杂社会经济系统计算研究的讨论.复杂系统与复杂性科学, 2004, 1(4):25-35 doi: 10.3969/j.issn.1672-3813.2004.04.002 Wang Fei-Yue. Artificial societies, computational experiments, and parallel systems:a discussion on computational theory of complex social-economic systems. Complex Systems and Complexity Science, 2004, 1(4):25-35 doi: 10.3969/j.issn.1672-3813.2004.04.002