A Coordination Technique for Improving Scalability of Byzantine Fault-Tolerant Consensus

Abstract

Among various consensus algorithms, the Byzantine Fault Tolerance (BFT)-based consensus algorithms are broadly used for private blockchain. However, as BFT-based consensus algorithms are structured for all participants to take part in a consensus process, a scalability issue becomes more noticeable. In this approach, we introduce a consensus coordinator to execute a conditionally BFT-based consensus algorithm by classifying transactions. Transactions are divided into equal and unequal transactions. Moreover, unequal transactions are divided again and classified as common and trouble transactions. After that, a consensus algorithm is only executed for trouble transactions, and BFT-based consensus algorithms can achieve scalability. For evaluating our approach, we carried out three experiments in response to three research questions. By applying our approach to PBFT, we obtained 4.75 times better performance than using only PBFT. In the other experiment, we applied our approach to IBFT of Hyperledger Besu, and our result shows a 61.81% performance improvement. In all experiments depending on the change of the number of blockchain nodes, we obtained the better performance than original BFT-based consensus algorithms; thus, we can conclude that our approach improved the scalability of original BFT-based consensus algorithms. We also showed a correlation between performance and trouble transactions associated with transaction issue intervals and the number of blockchain nodes.

Enhancing computational scalability in Blockchain by leveraging improvement in consensus algorithm

“…Importantly, decentralized systems are uniquely susceptible to the Byzantine Generals Problem due to their lack of a trustworthy information source and the inability to verify data from other members, relying solely on a central authority (Bentov et al, 2014). Another pivotal contribution was the introduction of the Proof-of-Work (PoW) consensus algorithm, inspired by Adam Back's Hash Cash proposal from 2002, aimed initially at mitigating email spam and denial-of-service attacks (Seo et al, 2020). PoW served as the foundational mechanism for Bitcoin, predicated on solving computationally intensive hash problems, rendering block modifications practically infeasible without rehashing all subsequent blocks.…”

An Efficient and Secure Blockchain Consensus Protocol for Internet of Vehicles

“…Ref. [7] categorizes transactions into equal and unequal transactions, only publicly disclosing erroneous transactions, thereby reducing the number of consensus iterations and increasing the efficiency and scalability of blockchain consensus. The consensus coordinator used in this approach is centralized, which may face single point of failure issues.…”

“…where R represents the matrix of routing hop count between nodes, and r i,j represents the routing hop count between nodes i and j (when i equals j, r i,j denotes the hop count between the node and itself, which is 0). Similarly, the distance between nodes can be expressed using Formula (7).…”

A multi-blockchain system application based on improved PBFT consensus mechanism for online rumor co-governance

“…For the problems of PBFT consensus algorithm, Seoet al proposed a consensus algorithm based on the coordinator, which classifies transactions through the coordinator and only executes complete consensus on abnormal transactions [25] . After applying this algorithm to PBFT, the performance has been improved by 4.75 times, but this algorithm may face the problem of system failure caused by a single point of failure of the coordinator.…”