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arXiv · 2102.09594

Embedding a Deterministic BFT Protocol in a Block DAG

Maria A Schett·George Danezis
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Abstract

This work formalizes the structure and protocols underlying recent distributed systems leveraging block DAGs, which are essentially encoding Lamport's happened-before relations between blocks, as their core network primitives. We then present an embedding of any deterministic Byzantine fault tolerant protocol $\mathcal{P}$ to employ a block DAG for interpreting interactions between servers. Our main theorem proves that this embedding maintains all safety and liveness properties of $\mathcal{P}$. Technically, our theorem is based on the insight that a block DAG merely acts as an efficient reliable point-to-point channel between instances of P while also using $\mathcal{P}$ for efficient message compression.

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Maria A Schett, George Danezis. 2021-02-18. Embedding a Deterministic BFT Protocol in a Block DAG. https://doi.org/10.1145/3465084.3467930

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