Cluster-Based PBFT Blockchain Consensus Modelling with Jackson Open Queuing Network

With the expansion of applications and areas of blockchains, there is an increasing need for faster transaction validation platforms. The Practical Byzantine Fault Tolerance (PBFT) algorithm is one of the best validation processes to meet the need for velocity and security of successful consensus. Despite the implementations in several platforms such as Hyperledger Fabric, the performance does not reach what was hoped for their consensuses. The objective of this paper is to present a performance evaluation model based on an Open Queuing Network to study the limits of PBFT and pipelined PBFT and to succeed in presenting a new parallelization approach in the form of parallel clusters. The advantage of this model is that it closely evaluates the different stages of PBFT execution according to the load submitted by the clients. This model is validated with the ns-3 simulator and has the advantage of quickly reaching evaluations that the simulator is limited in time to have them. The results show the importance of having consensus executions on parallel clusters to distribute the loads between nodes and clients. With cluster-based parallel PBFT, we can reach even twenty thousand transactions per second close to the validation values of Visa transactions. This opens the horizons towards the effective use of blockchains for new types of fast applications.