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arXiv · 2202.09123

Make Every Word Count: Adaptive BA with Fewer Words

Shir Cohen·Idit Keidar·Alexander Spiegelman
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Abstract

Byzantine Agreement is a key component in many distributed systems. While Dolev and Reischuk have proven a long time ago that quadratic communication complexity is necessary for worst-case runs, the question of what can be done in practically common runs with fewer failures remained open. In this paper we present the first Byzantine Broadcast algorithm with $O(n(f+1))$ communication complexity, where $0\leq f\leq t$ is the actual number of process failures in a run. And for BA with strong unanimity, we present the first optimal-resilience algorithm that has linear communication complexity in the failure-free case and a quadratic cost otherwise.

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Shir Cohen, Idit Keidar, Alexander Spiegelman. 2022-02-18. Make Every Word Count: Adaptive BA with Fewer Words. https://arxiv.org/abs/2202.09123

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