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arXiv · 2112.09437

Detectable Quantum Byzantine Agreement for Any Arbitrary Number of Dishonest Parties

Vicent Cholvi
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Abstract

Reaching agreement in the presence of arbitrary faults is a fundamental problem in distributed computation, which has been shown to be unsolvable if one-third of the processes can fail, unless signed messages are used. In this paper, we propose a solution to a variation of the original BA problem, called Detectable Byzantine Agreement (DBA), that does not need to use signed messages. The proposed algorithm uses what we call $Q$-correlated lists, which are generated by a quantum source device. Once each process has one of these lists, they use them to reach the agreement in a classical manner. Although, in general, the agreement is reached by using $m+1$ rounds (where $m$ is the number of processes that can fail), if less than one-third of the processes fail it only needs one round to reach the agreement.

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Vicent Cholvi. 2021-12-17. Detectable Quantum Byzantine Agreement for Any Arbitrary Number of Dishonest Parties. https://arxiv.org/abs/2112.09437

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