Paper 2021/1386
Efficient Threshold-Optimal ECDSA
Michaella Pettit
Abstract
This paper proposes a threshold-optimal ECDSA scheme based on the first threshold signature scheme by Gennaro et al. with efficient non-interactive signing for any $t+1$ signers in the group, provided the total group size is more than twice the threshold $t$. The scheme does not require any homomorphic encryption or zero-knowledge proofs and is proven to be robust and unforgeable with identifiable aborts tolerating at most $t$ corrupted participants. The security of the scheme is proven in a simulation-based definition, assuming DDH and that ECDSA is existentially unforgeable under chosen message attack. To evaluate the performance of the protocol, it has been implemented in C++ and the results demonstrate the non-interactive signing phase takes 0.12ms on average meaning over 8000 signatures can be created per second. With pre-signing phase, it takes 3.35ms in total, which is over 144 times faster than the current state of the art.
Metadata
- Available format(s)
-
PDF
- Category
- Public-key cryptography
- Publication info
- Published elsewhere. Minor revision. CANS2021
- Keywords
- ECDSAMultiparty computationThreshold signatures
- Contact author(s)
- m pettit @ nchain com
- History
- 2021-10-15: received
- Short URL
- https://ia.cr/2021/1386
- License
-
CC BY
BibTeX
@misc{cryptoeprint:2021/1386,
author = {Michaella Pettit},
title = {Efficient Threshold-Optimal ECDSA},
howpublished = {Cryptology ePrint Archive, Paper 2021/1386},
year = {2021},
note = {\url{https://eprint.iacr.org/2021/1386}},
url = {https://eprint.iacr.org/2021/1386}
}
