Paper 2023/397
Extended Abstract: HotStuff-2: Optimal Two-Phase Responsive BFT
Abstract
In this paper, we observe that it is possible to solve partially-synchronous BFT and simultaneously achieves $O(n^2)$ worst-case communication, optimistically linear communication, a two-phase commit regime within a view, and optimistic responsiveness. Prior work falls short in achieving one or more of these properties, e.g., the most closely related work, HotStuff, requires a three-phase view while achieving all other properties. We demonstrate that these properties are achievable through a two-phase HotStuff variant named HotStuff-2. The quest for two-phase HotStuff variants that achieve all the above desirable properties has been long, producing a series of results that are yet sub-optimal and, at the same time, are based on somewhat heavy hammers. HotStuff-2 demonstrates that none of these are necessary: HotStuff-2 is remarkably simple, adding no substantive complexity to the original HotStuff protocol. The main takeaway is that two phases are enough for BFT after all.
Metadata
- Available format(s)
-
PDF
- Category
- Foundations
- Publication info
- Preprint.
- Keywords
- BFTCommunication complexityOptimistic Responsiveness
- Contact author(s)
-
dahliamalkhi @ gmail com
kartik1507 @ gmail com - History
- 2023-04-17: last of 5 revisions
- 2023-03-20: received
- See all versions
- Short URL
- https://ia.cr/2023/397
- License
-
CC0
BibTeX
@misc{cryptoeprint:2023/397,
author = {Dahlia Malkhi and Kartik Nayak},
title = {Extended Abstract: {HotStuff}-2: Optimal Two-Phase Responsive {BFT}},
howpublished = {Cryptology {ePrint} Archive, Paper 2023/397},
year = {2023},
url = {https://eprint.iacr.org/2023/397}
}
