Paper 2026/1520 Original: eprint.iacr.org/2026/1520 ↗
Quintus: Two-round Good-case Information Theoretic BFT for $n=5f+1$
Abstract
We present Quintus, information-theoretic BFT protocols for tolerating $f < n/5$ Byzantine faults among $n$ parties. We present two protocols: The first protocol, Quintus-Fixed, is in a fixed view regime where views advance at a cadence $3\Delta$ time. This protocol incurs a good-case latency of $2\delta$ time where $\delta$ indicates actual network delay and message complexity of $O(n^2)$ in a view. The second protocol, Quintus-Responsive, is an optimistically responsive protocol with good-case latency of $2\delta$ time, $O(n^2)$ message complexity, and $2\Delta + 2\delta$ worst-case view latency where $\Delta$ denotes a pessimistic network delay parameter under synchrony.
Metadata
- Available format(s)
PDF- Category
- Cryptographic protocols
- Publication info
- Preprint.
- History
- 2026-10-06: last updated
- 2026-07-24: published
- Short URL
- https://ia.cr/2026/1520
- License
- https://creativecommons.org/licenses/by/4.0/
BibTeX
@misc{cryptoeprint:2026/1520,
author = {Chenyang Liu and Dahlia Malkhi and Kartik Nayak and Nibesh Shrestha},
title = {Quintus: Two-round Good-case Information Theoretic BFT for $n=5f+1$},
howpublished = {Cryptology {ePrint} Archive, Paper 2026/1520},
year = {2026},
url = {https://eprint.iacr.org/2026/1520}
}