Orthrus: Accelerating Multi-BFT Consensus through Concurrent Partial Ordering of Transactions

2024-12-09

AI Summary

Multi-BFT consensus alleviates leader bottlenecks via parallel instances but incurs high confirmation latency and limited concurrency due to enforced global ordering. This paper proposes a hybrid ordering paradigm: strongly sequence-dependent transactions retain global order, while others are dynamically partitioned based on dependency graphs and executed under partial order. A lightweight escrow protocol coordinates interactions across ordering domains while guaranteeing consistency. Our approach introduces the first synergistic mechanism integrating partial and global ordering, enabling dynamic partitioning and asynchronous cross-domain coordination. In wide-area network experiments with 128 nodes, it reduces maximum confirmation latency by up to 87% compared to state-of-the-art Multi-BFT protocols, while significantly improving throughput and real-time responsiveness.

Technology Category

• Multiagent Systems: Coordination and Collaboration
• Game Theory and Economic Paradigms: Coordination and Collaboration
• Search and Optimization: Distributed Search

Application Category

• Security and Privacy: Large-scale security measurements
• Systems and Infrastructure for Web, Mobile and WoT: Decentralized Web and Fediverse systems
• Economics, Online Markets and Human Computation: Incentives in network design for Web infrastructures and ecosystems

Abstract

Multi-Byzantine Fault Tolerant (Multi-BFT) consensus allows multiple consensus instances to run in parallel, resolving the leader bottleneck problem inherent in classic BFT consensus. However, the global ordering of Multi-BFT consensus enforces a strict serialized sequence of transactions, imposing additional confirmation latency and also limiting concurrency. In this paper, we introduce Orthrus, a Multi-BFT protocol that accelerates transaction confirmation through partial ordering while reserving global ordering for transactions requiring stricter sequencing. To this end, Orthrus strategically partitions transactions to maximize concurrency and ensure consistency. Additionally, it incorporates an escrow mechanism to manage interactions between partially and globally ordered transactions. We evaluated Orthrus through extensive experiments in realistic settings, deploying 128 replicas in WAN and LAN environments. Our findings demonstrate latency reductions of up to 87% in WAN compared to existing Multi-BFT protocols.

Problem

• Accelerates Multi-BFT consensus transactions
• Reduces latency through partial ordering
• Enhances concurrency with strategic transaction partitioning

Innovation

• Partial ordering accelerates transactions
• Escrow mechanism manages transaction interactions
• Strategic partitioning maximizes concurrency