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arXiv · 1908.00427

Bitcoin Security under Temporary Dishonest Majority

Georgia Avarikioti·Lukas Kaeppeli·Yuyi Wang·Roger Wattenhofer
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Abstract

We prove Bitcoin is secure under temporary dishonest majority. We assume the adversary can corrupt a specific fraction of parties and also introduce crash failures, i.e., some honest participants are offline during the execution of the protocol. We demand a majority of honest online participants on expectation. We explore three different models and present the requirements for proving Bitcoin's security in all of them: we first examine a synchronous model, then extend to a bounded delay model and last we consider a synchronous model that allows message losses.

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Georgia Avarikioti, Lukas Kaeppeli, Yuyi Wang, Roger Wattenhofer. 2019-08-01. Bitcoin Security under Temporary Dishonest Majority. https://arxiv.org/abs/1908.00427

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