Crux—A New Fast, Flexible and Decentralized Consensus Algorithm with High Fault Tolerance Rate

  • Pengfei LiEmail author
  • Jingtian Peng
  • Long Yang
  • Qian Zheng
  • Gang Pan
Conference paper
Part of the Lecture Notes in Computer Science book series (LNCS, volume 11373)


This paper presents Crux, a new permissionless blockchain consensus algorithm that achieves higher fault tolerance rate with more flexibility than existing blockchains such as Bitcoin, Ethereum and EOS. Crux utilize a DPoS-XPaxos pipelined algorithm to achieve effective and efficient consensus. Those who hold tokens in Crux elect \(2f+1\) block producers called validators through a continuous approval voting system. The elected validators are scheduled in an order and produce blocks in turns agreed by all of the validators. XPaxos, guarantees \(\frac{f}{2f+1}\) fault tolerance rate, is added to traditional DPoS to confirm blocks. Once \(f+1\) validators have signed a block, it is deemed irreversible. Analysis shows Crux provides higher securities, better flexibility, higher TPS (transaction per second) with little cost of centralization compared with existing blockchain consensus algorithms.


Blockchain Consensus algorithm DPoS XPaxos Fault tolerance 


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Copyright information

© Springer Nature Switzerland AG 2018

Authors and Affiliations

  • Pengfei Li
    • 1
    • 2
    Email author
  • Jingtian Peng
    • 1
  • Long Yang
    • 2
  • Qian Zheng
    • 3
  • Gang Pan
    • 2
  1. 1.LD ResearchShanghaiChina
  2. 2.Zhejiang UniversityHangzhouChina
  3. 3.Nanyang Technological UniversitySingaporeSingapore

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