Optimizing Communication in Byzantine Agreement Protocols with Slim-HBBFT

2025-11-19

AI Summary

Traditional asynchronous Byzantine Fault-Tolerant (BFT) atomic broadcast protocols incur excessive communication overhead—O(n²) per request—due to global broadcasting of all client requests, leading to redundant transmissions and resource waste. Method: This paper proposes Slim-HBBFT, a novel protocol centered on Priority-Provable Broadcast (P-PB), wherein only a designated subset of nodes generates lightweight broadcast proofs, reducing per-request communication complexity to O(n) while strictly satisfying the safety and liveness requirements of Asynchronous Common Subset (ACS). Slim-HBBFT integrates asynchronous BFT, provable broadcast, and priority-based scheduling, and its correctness is formally verified. Contribution/Results: Experimental evaluation demonstrates that Slim-HBBFT achieves significantly higher throughput and lower latency under high-concurrency workloads, establishing a new paradigm for efficient and secure distributed consensus in asynchronous settings.

Technology Category

• Multiagent Systems: Mechanism Design
• Search and Optimization: Distributed Search
• Data Mining & Knowledge Management: Scalability, Parallel & Distributed Systems

Application Category

• Security and Privacy: Large-scale security measurements
• Systems and Infrastructure for Web, Mobile and WoT: Web performance, measurement, and characterization
• Graph Algorithms and Modeling for the Web: Efficient manipulation of static and dynamic Web-related graphs

Abstract

Byzantine agreement protocols in asynchronous networks have received renewed interest because they do not rely on network behavior to achieve termination. Conventional asynchronous Byzantine agreement protocols require every party to broadcast its requests (e.g., transactions), and at the end of the protocol, parties agree on one party's request. If parties agree on one party's requests while exchanging every party's request, the protocol becomes expensive. These protocols are used to design an atomic broadcast (ABC) protocol where parties agree on $langle n-f angle$ parties' requests (assuming $n=3f+1$, where $n$ is the total number of parties, and $f$ is the number of Byzantine parties). Although the parties agree on a subset of requests in the ABC protocol, if the requests do not vary (are duplicated), investing in a costly protocol is not justified. We propose Slim-HBBFT, an atomic broadcast protocol that considers requests from a fraction of $n$ parties and improves communication complexity by a factor of $O(n)$. At the core of our design is a prioritized provable-broadcast (P-PB) protocol that generates proof of broadcast only for selected parties. We use the P-PB protocol to design the Slim-HBBFT atomic broadcast protocol. Additionally, we conduct a comprehensive security analysis to demonstrate that Slim-HBBFT satisfies the properties of the Asynchronous Common Subset protocol, ensuring robust security and reliability.

Problem

• Reduces communication costs in Byzantine agreement protocols
• Optimizes atomic broadcast by selecting fraction of parties
• Ensures security through prioritized provable-broadcast protocol

Innovation

• Uses prioritized provable-broadcast for selected parties
• Reduces communication complexity by factor of O(n)
• Considers requests from fraction of n parties