2-hop Blockchain: Combining Proof-of-Work and Proof-of-Stake Securely

@inproceedings{Duong20202hopBC,
  title={2-hop Blockchain: Combining Proof-of-Work and Proof-of-Stake Securely},
  author={Tuyet Duong and Lei Fan and Jonathan Katz and Phuc Thai and Hong-Sheng Zhou},
  booktitle={ESORICS},
  year={2020}
}
Bitcoin-like blockchains use a proof-of-work (PoW) mechanism, where security holds if the majority of the computing power is under the control of honest players. However, this assumption has been seriously challenged recently, and Bitcoin-like systems fail if this assumption is violated. In this work we propose a novel 2-hop blockchain protocol that combines PoW and proof-of-stake (PoS) mechanisms. Our analysis shows that the protocol is secure as long as the honest players control a majority… 

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