Dynamic PBFT with Active Removal

The Practical Byzantine Fault Tolerance (PBFT) consensus in permissioned blockchains is known for its strong consistency and engineering feasibility. However, research on dynamic node join/leave processes and robustness is limited. This study presents an active removal dynamic PBFT algorithm, utilizing atomic broadcast technology for a provably secure dynamic broadcast primitive and a K-Nearest Neighbors (KNN) based malicious node classification and removal protocol. This enables PBFT consensus to accommodate dynamic requirements while mitigating voting power attacks and malicious nodes. Results show maintained system performance during dynamic node changes, accurate malicious behavior detection, and prompt node removal, addressing current PBFT limitations and enhancing blockchain network robustness.