Blockchain Consensus Algorithm Design Based on Consistent Hash Algorithm

Abstract

Blockchain, the concept from Bitcoin created by Satoshi Nakamoto, has the potential to decentralise traditionally centralised systems. Blockchain is a distributed ledger for recording information, stored by many nodes without a central organization through distributed systems and cryptography. The consensus algorithm is a protocol that guarantees the consistency of all data in a blockchain system. It is a key for building a blockchain system and an important part that affects the performance of the blockchain system. In this paper, we firstly compare the usage scenarios of different consensus algorithms, their advantages and disadvantages. After that, we present a new consensus algorithm in permissioned blockchain based on consistent hashing. For blockchain system construction, we propose a new design of the hash ring. The pseudo-randomness of the hash operation is used to ensure the randomness of the electoral leadership node in the blockchain system. It avoids the security risk of the fixed leadership node model. Our algorithm is applicable to blockchain systems containing Byzantine nodes and has a high throughput, low delay and many other advantages. Its communication complexity is O(n), significantly better than that of the practical Byzantine fault tolerance algorithm whose communication complexity is O(n2).