Fully Decentralised Consensus for Extreme-scale Blockchain

Blockchain is a decentralised, immutable ledger technology that has been widely adopted in many sectors for various applications such as cryptocurrencies, smart contracts and supply chain management. Distributed consensus is a fundamental component of blockchain, which is required to ensure trust, security, and integrity of the data stored and the transactions processed in the blockchain. Various consensus algorithms have been developed, each suffering from certain issues such as node failures, high resource consumption, collusion, etc. This work introduces the Blockchain Epidemic Consensus Protocol (BECP), adopting a fully decentralised consensus approach suitable for very large and extreme-scale blockchain systems. BECP leverages the benefits of epidemic protocols, such as no reliance on a fixed set of validators or leaders, probabilistic guarantees of convergence, efficient use of network resources, and tolerance to node and network failures. A comparative experimental analysis has been carried out with traditional protocols including PAXOS, RAFT, and Practical Byzantine Fault Tolerant (PBFT), as well as a more recent protocol such as Avalanche, which is specifically designed for very large-scale systems. The results illustrate how BECP outperforms them in terms of throughput, scalability and consensus latency. BECP achieves an average of 1.196 times higher throughput in terms of consensus on items and 4.775 times better average consensus latency. Furthermore, BECP significantly reduces the number of messages compared to Avalanche. These results demonstrate the effectiveness and efficiency of BECP and indicate its potential as a significant advancement in decentralised consensus for blockchain technology.