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arXiv · 1801.07965

Winning the Caucus Race: Continuous Leader Election via Public Randomness

Sarah Azouvi·Patrick McCorry·Sarah Meiklejohn
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Abstract

Consensus protocols inherently rely on the notion of leader election, in which one or a subset of participants are temporarily elected to authorize and announce the network's latest state. While leader election is a well studied problem, the rise of distributed ledgers (i.e., blockchains) has led to a new perspective on how to perform large-scale leader elections via solving a computationally difficult puzzle (i.e., proof of work). In this paper, we present Caucus, a large-scale leader election protocol with minimal coordination costs that does not require the computational cost of proof-of-work. We evaluate Caucus in terms of its security, using a new model for blockchain-focused leader election, before testing an implementation of Caucus on an Ethereum private network. Our experiments highlight that one variant of Caucus costs only $0.10 per leader election if deployed on Ethereum.

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Sarah Azouvi, Patrick McCorry, Sarah Meiklejohn. 2018-01-24. Winning the Caucus Race: Continuous Leader Election via Public Randomness. https://arxiv.org/abs/1801.07965

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