Paper 2019/456

UniqueChain: A Fast, Provably Secure Proof-of-Stake Based Blockchain Protocol in the Open Setting

Peifang Ni, Hongda Li, Xianning Meng, and Dongxue Pan


We present UniqueChain, a proof-of-stake based blockchain protocol that is secure against a mildly adaptive adversary in open setting, where newly joining parties can be initialized securely without any additional trusted assumptions. What's more, UniqueChain provides secure best local chains for existing honest parties and achieves fast messages (transactions) confirmation. Security of protocol holds if majority of overall stakes are controlled by honest parties. To achieve the above guarantees, we formalize a secure bootstrapping mechanism for new parties, a best local chain selection rule for existing honest parties and propose a new form of two-chain structure that realizes uniqueness of the chains, which contain messages, held by honest parties. Further, we prove that $UniqueChain$ satisfies security properties as chain growth, chain quality, common prefix and soundness, and two additional properties as uniqueness and high efficiency.

Available format(s)
Cryptographic protocols
Publication info
Preprint. Minor revision.
proof-of-stakesecure initializationuniquenesshigh efficiency
Contact author(s)
nipeifang @ iie ac cn
2019-05-14: revised
2019-05-10: received
See all versions
Short URL
Creative Commons Attribution


      author = {Peifang Ni and Hongda Li and Xianning Meng and Dongxue Pan},
      title = {UniqueChain: A Fast, Provably Secure Proof-of-Stake Based Blockchain Protocol in the Open Setting},
      howpublished = {Cryptology ePrint Archive, Paper 2019/456},
      year = {2019},
      note = {\url{}},
      url = {}
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