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arXiv · 1510.02037

Bitcoin-NG: A Scalable Blockchain Protocol

Ittay Eyal·Adem Efe Gencer·Emin Gun Sirer·Robbert van Renesse
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Abstract

Cryptocurrencies, based on and led by Bitcoin, have shown promise as infrastructure for pseudonymous online payments, cheap remittance, trustless digital asset exchange, and smart contracts. However, Bitcoin-derived blockchain protocols have inherent scalability limits that trade-off between throughput and latency and withhold the realization of this potential. This paper presents Bitcoin-NG, a new blockchain protocol designed to scale. Based on Bitcoin's blockchain protocol, Bitcoin-NG is Byzantine fault tolerant, is robust to extreme churn, and shares the same trust model obviating qualitative changes to the ecosystem. In addition to Bitcoin-NG, we introduce several novel metrics of interest in quantifying the security and efficiency of Bitcoin-like blockchain protocols. We implement Bitcoin-NG and perform large-scale experiments at 15% the size of the operational Bitcoin system, using unchanged clients of both protocols. These experiments demonstrate that Bitcoin-NG scales optimally, with bandwidth limited only by the capacity of the individual nodes and latency limited only by the propagation time of the network.

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Ittay Eyal, Adem Efe Gencer, Emin Gun Sirer, Robbert van Renesse. 2015-11-11. Bitcoin-NG: A Scalable Blockchain Protocol. https://arxiv.org/abs/1510.02037

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