An Effective and Robust Transaction Packaging Approach for Multi-leader BFT Blockchain Systems
Wenbin Wang, Xiulong Liu, Hao Xu, Wenyu Qu · 2023
Byzantine fault-tolerant (BFT) consensus ensures system consistency in the presence of malicious replicas and is widely adopted in blockchain systems. To enhance scalability and throughput, recent advancements incorporate multiple leaders into BFT consensus. However, employing multiple leaders results in significant resource wastage in terms of storage, bandwidth, and CPU usage, attributable to transaction redundancy. Conversely, to eliminate duplication, the resilience in Byzantine settings is compromised. To bridge this gap, we propose PeterHofe, a novel ring-based collaborative transaction packaging method, aiming to maintain resource efficiency and minimize Byzantine leader influence, thereby reducing transaction latency and improving system robustness. PeterHofe extends the concept of partitioning transaction hash space into buckets, establishing many-to-many mappings between replicas and buckets to diminish Byzantine replica control. When implementing PeterHofe, we address the following two challenges. 1) To improve resistance to Byzantine censorship, we design a permutation-based ring structure with accompanying correctness proofs and mathematical analyses; 2) To further reduce transaction duplication, we introduce a Prophecy-Implementation mechanism with analyzed malicious behaviors. We implement PeterHofe on top of the latest and representative work, Narwhal and Tusk. Experimental results demonstrate that PeterHofe can achieve low resource waste and high system robustness simultaneously. Specifically, PeterHofe's resource waste rate is near 5~17% in general cases, which is a 20-fold reduction compared to the Random-based Strategy; compared with the state-of-the-art Hash-based Partitioning Strategy, the proportion of maliciously controlled transactions is reduced by at least 66%, leading to a latency decrease of up to 75%.