Threshold ECDSA in Three Rounds

 title = {Threshold ECDSA in Three Rounds},
 author = {Jack Doerner and Yash Kondi and Eysa Lee and abhi shelat},
 howpublished = {eprint/2023/765},
 year = {2023},

eprint 2023/765

We present a three-round protocol for threshold ECDSA signing with malicious security against a dishonest majority, which information-theoretically UC-realizes a standard threshold signing functionality, assuming ideal commitment and two-party multiplication primitives. Our work improves upon and fully subsumes the DKLs $t$-of-$n$ and $2$-of-$n$ protocols. This document focuses on providing a succinct but complete description of the protocol and its security proof.