Bitcoin-NG: A Scalable Blockchain Protocol

TL;DR

Bitcoin-NG is a new scalable blockchain protocol that improves throughput and latency, maintaining Bitcoin's trust model and robustness, demonstrated through large-scale experiments showing optimal scalability.

Contribution

Introduces Bitcoin-NG, a scalable blockchain protocol based on Bitcoin, with novel metrics for security and efficiency, validated through extensive experiments.

Findings

Bitcoin-NG achieves near-optimal scalability in throughput and latency.

The protocol maintains Bitcoin's security and trust assumptions.

Experimental results show Bitcoin-NG's performance at 15% of Bitcoin's size.

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.