Using Level-1 Homomorphic Encryption to Improve Threshold DSA Signatures for Bitcoin Wallet Security

@inproceedings{Boneh2017UsingLH,
  title={Using Level-1 Homomorphic Encryption to Improve Threshold DSA Signatures for Bitcoin Wallet Security},
  author={Dan Boneh and Rosario Gennaro and Steven Goldfeder},
  booktitle={International Conference on Cryptology and Information Security in Latin America},
  year={2017}
}
Recently Gennaro et al. (ACNS ’16) presented a threshold-optimal signature algorithm for DSA. Threshold-optimality means that if security is set so that it is required to have \(t+1\) servers to cooperate to sign, then it is sufficient to have \(n=t+1\) honest servers in the network. Obviously threshold optimality compromises robustness since if \(n=t+1\), a single corrupted player can prevent the group from signing. Still, in their protocol, up to t corrupted players cannot produce valid… 

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