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arXiv · 2501.15904

Snowman for partial synchrony

Aaron Buchwald·Stephen Buttolph·Andrew Lewis-Pye·Kevin Sekniqi
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Abstract

Snowman is the consensus protocol run by blockchains on Avalanche. Recent work established a rigorous proof of probabilistic consistency for Snowman in the \emph{synchronous} setting, under the simplifying assumption that correct processes execute sampling rounds in `lockstep'. In this paper, we describe a modification of the protocol that ensures consistency in the \emph{partially synchronous} setting, and when correct processes carry out successive sampling rounds at their own speed, with the time between sampling rounds determined by local message delays.

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Aaron Buchwald, Stephen Buttolph, Andrew Lewis-Pye, Kevin Sekniqi. 2025-01-27. Snowman for partial synchrony. https://arxiv.org/abs/2501.15904

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