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arXiv · 1909.06587

An Analysis of Blockchain Consistency in Asynchronous Networks: Deriving a Neat Bound

Abstract

Formal analyses of blockchain protocols have received much attention recently. Consistency results of Nakamoto's blockchain protocol are often expressed in a quantity $c$, which denotes the expected number of network delays before some block is mined. With $μ$ (resp., $ν$) denoting the fraction of computational power controlled by benign miners (resp., the adversary), where $μ+ ν= 1$, we prove for the first time that to ensure the consistency property of Nakamoto's blockchain protocol in an asynchronous network, it suffices to have $c$ to be just slightly greater than $\frac{2μ}{\ln (μ/ν)}$. Such a result is both neater and stronger than existing ones. In the proof, we formulate novel Markov chains which characterize the numbers of mined blocks in different rounds.

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Jun Zhao, Jing Tang, Li Zengxiang, Huaxiong Wang, Kwok-Yan Lam, Kaiping Xue. 2020-03-13. An Analysis of Blockchain Consistency in Asynchronous Networks: Deriving a Neat Bound. https://arxiv.org/abs/1909.06587

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