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arXiv · 2105.13487

Multidimensional Byzantine Agreement in a Synchronous Setting

Andrea Flamini·Riccardo Longo·Alessio Meneghetti
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Abstract

In this paper we will present the Multidimensional Byzantine Agreement (MBA) Protocol, a leaderless Byzantine agreement protocol defined for complete and synchronous networks that allows a network of nodes to reach consensus on a vector of relevant information regarding a set of observed events. The consensus process is carried out in parallel on each component, and the output is a vector whose components are either values with wide agreement in the network (even if no individual node agrees on every value) or a special value $\bot$ that signals irreconcilable disagreement. The MBA Protocol is probabilistic and its execution halts with probability 1, and the number of steps necessary to halt follows a Bernoulli-like distribution. The design combines a Multidimensional Graded Consensus and a Multidimensional Binary Byzantine Agreement, the generalization to the multidimensional case of two protocols by Micali and Feldman. We prove the correctness and security of the protocol assuming a synchronous network where less than a third of the nodes are malicious.

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Andrea Flamini, Riccardo Longo, Alessio Meneghetti. 2021-05-27. Multidimensional Byzantine Agreement in a Synchronous Setting. https://arxiv.org/abs/2105.13487

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