Bitcoin-NG: A Scalable Blockchain Protocol
This addresses scalability issues for users of cryptocurrencies like Bitcoin, enabling higher throughput and lower latency without changing the trust model, though it builds incrementally on Bitcoin's protocol.
The paper tackles the inherent scalability limits of Bitcoin-derived blockchain protocols by introducing Bitcoin-NG, a new protocol that achieves optimal scaling with throughput limited only by node capacity and latency limited only by network propagation time.
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.