许可链多中心动态共识机制  

Permissioned Blockchain Dynamic Consensus Mechanism Based Multi-Centers

作　　者：闵新平 李庆忠[1,2] 孔兰菊 张世栋[1,2] 郑永清[1,2] 肖宗水 MIN Xin-Ping;LI Qing-Zhong;KONG Lan-Ju;ZHANG Shi-Dong;ZHENG Yong-Qing;XIAO Zong-Shui(School of Computer Science and Technology,Shandong University,Jinan 250101;Electronic Commerce Research Center of Shandong University,Jinan 250101;Dareway Software Co.,Ltd.,Jinan 250101)

机构地区：[1]山东大学计算机科学与技术学院,济南250101 [2]山大地纬软件股份有限公司,济南250101 [3]山东大学电子商务研究中心,济南250101

出　　处：《计算机学报》2018年第5期1005-1020,共16页Chinese Journal of Computers

基　　金：国家自然科学基金(61772316);泰山产业领军人才专项(tscy20160404);山东省重点研发计划(2017CXGC0702)资助~~

摘　　要：区块链技术可解决数字化资产可信度低下问题,但大多数解决方案存在交易吞吐量低下、共识延迟过高、通信代价高、难以保证数字化资产全局一致性等方面的限制.许可区块链系统由高可信的节点组成,对特定组织开放,拥有相对良好的网络环境,为区块链的性能扩展提供了新的选择.为支持许可环境中多中心的需求,该文提出许可链多中心动态共识机制,设计两层区块链结构,构建主从多链,通过全局区块链链接多个主体区块链,保证数字化资产的全局一致性,提高区块链性能.通过引入全局区块与主体区块实现交易分流,提高交易吞吐量;通过生成动态验证节点集,设计全局一致性验证模型保证数字化资产的全局一致性;设计多主节点的PBFT协议,消除由恶意节点作为主节点带来的交易延迟增加问题.通过安全分析与证明,许可链多中心动态共识机制可保证交易不可篡改、预防Sybil攻击等;通过实验验证,许可链多中心动态共识机制可实现秒级交易延迟、十万级交易吞吐量.Existing solutions leverage blockchain protocols to improve the credibility of digital assets,such as bitcoin blockchain,Ethereum blockchain and Fabric blockchain.Most of blockchain protocols still have significant scalability barriers,such as a higher communication cost,a higher latency,a lower throughput of transaction,a fixed block size and nonsupport of global consistency of digital assets.Permissioned blockchains are made up of highly trusted nodes,open to specific organizations,have a better communication network,and provide new ideas for improving the performance of the blockchain and supporting the global consistency of digital assets.To support the demand of permissioned multi-centers that each center is made up of multi nodes and each user can send any transactions on any centers,by constructing two-layer blockchain and introducing a master-slave blockchain,this paper presents an Permissioned Blockchain Dynamic Consensus Mechanism based Multi-Centers(PBCM),each center has a peer blockchain that keeps itself transactions and global blockchain keeps the abstract of trusted transaction from all centers,PBCM uses global blockchain to link with multi peer blockchains to improve the performance of permissioned blockchain,and by preventing user from sending multi transactions about the same digital asset at multi centers at the same time,PBCM can guarantee the global consistency of digital assets.By introducing global block and peer block,peer block contains the specific content of transactions and is proposed by each center,global block contains the abstract of trusted transactions and is proposed by global committee,each peer blockchain just keep itself transactions,PBCM can divide transactions into multi peer blockchains to improve the throughput of transactions and reduce the consensus latency of transactions.To guarantee the global consistency of digital assets,this paper presents a Global Transaction Validation Model(GTVM)by constructing dynamic validation group for each peer,the membership of each valid

关 键 词：区块链 共识机制 可信度 许可链 数字化资产 

分 类 号：TP309[自动化与计算机技术—计算机系统结构]