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arXiv · 2102.08325

All You Need is DAG

Idit Keidar·Eleftherios Kokoris-Kogias·Oded Naor·Alexander Spiegelman
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Abstract

We present DAG-Rider, the first asynchronous Byzantine Atomic Broadcast protocol that achieves optimal resilience, optimal amortized communication complexity, and optimal time complexity. DAG-Rider is post-quantum safe and ensures that all messages proposed by correct processes eventually get decided. We construct DAG-Rider in two layers: In the first layer, processes reliably broadcast their proposals and build a structured Directed Acyclic Graph (DAG) of the communication among them. In the second layer, processes locally observe their DAGs and totally order all proposals with no extra communication.

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Idit Keidar, Eleftherios Kokoris-Kogias, Oded Naor, Alexander Spiegelman. 2021-02-16. All You Need is DAG. https://arxiv.org/abs/2102.08325

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