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arXiv · 2012.00472

Byzantine Eventual Consistency and the Fundamental Limits of Peer-to-Peer Databases

Martin Kleppmann·Heidi Howard
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Abstract

Sybil attacks, in which a large number of adversary-controlled nodes join a network, are a concern for many peer-to-peer database systems, necessitating expensive countermeasures such as proof-of-work. However, there is a category of database applications that are, by design, immune to Sybil attacks because they can tolerate arbitrary numbers of Byzantine-faulty nodes. In this paper, we characterize this category of applications using a consistency model we call Byzantine Eventual Consistency (BEC). We introduce an algorithm that guarantees BEC based on Byzantine causal broadcast, prove its correctness, and demonstrate near-optimal performance in a prototype implementation.

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Martin Kleppmann, Heidi Howard. 2020-12-01. Byzantine Eventual Consistency and the Fundamental Limits of Peer-to-Peer Databases. https://arxiv.org/abs/2012.00472

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