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arXiv · 2002.03613

The Istanbul BFT Consensus Algorithm

Henrique Moniz
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Abstract

This paper presents IBFT, a simple and elegant Byzantine fault-tolerant consensus algorithm that is used to implement state machine replication in the \emph{Quorum} blockchain. IBFT assumes a partially synchronous communication model, where safety does not depend on any timing assumptions and only liveness depends on periods of synchrony. The algorithm is deterministic, leader-based, and optimally resilient - tolerating $f$ faulty processes out of $n$, where $n \geq 3f+1$. During periods of good communication, IBFT achieves termination in three message delays and has $O(n^2)$ total communication complexity.

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Henrique Moniz. 2020-02-10. The Istanbul BFT Consensus Algorithm. https://arxiv.org/abs/2002.03613

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