区块链系统在去中心化、安全性和可扩展性达到动态平衡的难点在于高效共识机制的设计.为解决现有区块链系统中共识机制面临的安全与性能的瓶颈问题，提出了一种基于权益代表的可扩展共识协议（delegate-based scalable consensus protocol，DSCP）.首先，DSCP采用分区并行共识方式来构建高性能和可拓展的区块链，并通过代理机制生成全网认可的共识区块；其次，为了提高网络分区速度和分区内的共识性能，提出了基于可验证随机函数（verifiable random function，VRF）算法的网络节点快速分区机制，设计了基于投票的分区共识算法（voting-based consensus protocol，VCP）；最后，提出了新的激励和押金机制，以增强DSCP协议的安全性.实验分析表明：与现有的区块链共识协议相比，DSCP有着良好的性能优势.
The difficulty in achieving dynamic balance of decentralization, security and scalability of blockchain systems lies in the design of efficient consensus mechanisms. In order to solve the bottleneck problem of security and performance faced by the consensus mechanisms in the existing blockchain systems, this paper proposes a delegate-based scalable consensus protocol (DSCP) based on equity representatives. First, DSCP uses the partition parallel consensus method to build a high-performance and scalable blockchain and generate a consensus block that is recognized by the entire network through a proxy mechanism. Then, in order to improve the network partition speed and the consensus performance during the partition, this paper proposes a fast partitioning mechanism based on VRF algorithm, and designs a voting-based partitioning high-performance consensus algorithm voting-based consensus protocol (VCP). At last, this paper also proposes a new incentive and deposit mechanism to enhance the security of the DSCP protocol. Experimental analysis shows that DSCP has a good performance advantage compared with the existing blockchain consensus protocols.
[1] Nakamoto S. Bitcoin:a peer-to-peer electronic cash system[OL]. https://bitcoin.org/bitcoin.pdf,2008.
[2] Sadouskaya K. Adoption of blockchain technologyin supply chain and logistics[OL]. https://www.theseus.fi/bitstream/handle/10024/126096/Adoption of Blockchain Technology in Supply Chain and Logistics.pdf?sequence=1, 2017.
[3] Zhang P, Schmidt D C, White J, et al. Blockchain technology use cases in healthcare[M]//Advances in Computers. Elsevier, 2018, 111:1-41.
[4] Novo O. Blockchain meets IoT:an architecture for scalable access management in IoT[J]. IEEE Internet of Things Journal, 2018, 5(2):1184-1195.
[5] Crain T, Gramoli V, Larrea M, et al. DBFT:efficient leaderless Byzantine consensus and its application to blockchains[C]//2018 IEEE 17th International Symposium on Network Computing and Applications (NCA). IEEE, 2018:1-8.
[6] Amoussou-Guenou Y, del Pozzo A, Potop-Butucaru M, et al. Dissecting tendermint[C]//International Conference on Networked Systems. Springer, Cham, 2019:166-182.
[7] Konstantinidis I, Siaminos G, Timplalexis C, et al. Blockchain for business applications:a systematic literature review[C]//International Conference on Business Information Systems. Cham:Springer, 2018:384-399.
[8] Luu L, Narayanan V, Baweja K, et al. SCP:a computationally-scalable Byzantine consensus protocol for blockchains[J]. IACR Cryptology ePrint Archive, 2015:1168.
[9] Li Z C, Huang J H, Gao D Q, et al. ISCP:an improved blockchain consensus protocol[J]. International Journal of Network Security, 2019, 21(3):359-367
[10] Saraf C, Sabadra S. Blockchain platforms:a compendium[C]//2018 IEEE International Conference on Innovative Research and Development (ICIRD). IEEE, 2018:1-6.
[11] Eyal I, Gencer A E, Sirer E G, et al. Bitcoin-NG:a scalable blockchain protocol[C]//13th{USENIX}Symposium on Networked Systems Design and Implementation ({NSDI}16). 2016:45-59.
[12] Poon J, Dryja T. The bitcoin lightning network:scalable off-chain instant payments[OL]. https://www.bitcoinlightning.com/wp-content/uploads/2018/03/lightning-network-paper.pdf, 2016.
[13] Gervais A, Karame G O, Wüst K, et al. On the security and performance of proof of work blockchains[C]//Proceedings of the 2016 ACM SIGSAC conference on computer and communications security. ACM, 2016:3-16.
[14] King S, Nadal S. PPCoin:peer-to-peer crypto-currency with proof-of-stake[J/OL]. https://peercoin.net/assets/paper/peercoin-paper.pdf.2017.
[15] Luo Y, Chen Y, Chen Q, et al. A new election algorithm for DPoS consensus mechanism in blockchain[C]//20187th International Conference on Digital Home (ICDH). IEEE, 2018:116-120.
[16] Chohan U W. The narcotized blockchain:a potcoin case study[J]. SSRN Electronic Journal, 2018, 28(1):201-207.
[17] Busse A, Eberhardt J, Frost S, et al. A response to the United Nations CITES blockchain challenge:incremental and integrative PoA-based permit exchange[C]//2019 IEEE International Conference on Blockchain and Cryptocurrency (ICBC). IEEE, 2019:320-328.
[18] Zheng Z, Xie S, Dai H N, et al. Blockchain challenges and opportunities:a survey[J]. International Journal of Web and Grid Services, 2018, 14(4):352-375.
[19] Bach L M, Mihaljevic B, Zagar M. Comparative analysis of blockchain consensus algorithms[C]//201841st International Convention on Information and Communication Technology, Electronics and Microelectronics (MIPRO). IEEE, 2018:1545-1550.
[20] Androulaki E, Barger A, Bortnikov V, et al. Hyperledger fabric:a distributed operating system for permissioned blockchains[C]//Proceedings of the Thirteenth EuroSys Conference. ACM, 2018:1-15.
[21] Makhdoom I, Abolhasan M, Ni W. Blockchain for IoT:the challenges and a way forward[C]//Proceedings of the 15th International Joint Conference on e-Business and Telecommunications-Volume 2, 2018.
[22] Dwork C, Lynch N, Stockmeyer L. Consensus in the presence of partial synchrony[J]. Journal of the ACM, 1988, 35(2):288-323.
[23] Sheth N, Prajapati P, Shaikh A, et al. Casper:modification of bitcoin using proof of stake[M]//Information and Communication Technology for Intelligent Systems. Singapore:Springer, 2019:79-85.
