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arXiv · 1909.06587

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

Jun Zhao·Jing Tang·Li Zengxiang·Huaxiong Wang·Kwok-Yan Lam·Kaiping Xue
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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 $\mu$ (resp., $\nu$) denoting the fraction of computational power controlled by benign miners (resp., the adversary), where $\mu + \nu = 1$, 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 $\frac{2\mu}{\ln (\mu/\nu)}$. 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. 2019-09-14. An Analysis of Blockchain Consistency in Asynchronous Networks: Deriving a Neat Bound. https://arxiv.org/abs/1909.06587

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