Fides: 通过可信组件实现安全且可扩展的异步DAG共识
Fides: Secure and Scalable Asynchronous DAG Consensus via Trusted Components
AI总结：
提出基于DAG的异步BFT共识协议Fides，利用TEE优化可靠广播原语，将元数据通信复杂度降至O(κn²+n³)，并通过重新定义DAG构建规则和四轮提交规则实现理论最小提交延迟，在分布式测试中显著优于现有协议。
摘要：
基于DAG的BFT共识因其高吞吐量和异步容错性，在非可信环境下的分布式数据管理系统中引起了越来越多的关注。然而，现有协议仍存在通信开销高和提交延迟长的问题。同时，引入最小硬件信任已被证明能有效降低BFT共识的复杂度。受这些工作的启发，我们提出了Fides，一种基于DAG的异步BFT共识协议，据我们所知，这是首批利用TEE来增强可扩展性和效率的协议之一。Fides容忍少数拜占庭副本，并通过定制的TEE辅助可靠广播（T-RBC）原语实现了O(κn²+n³)的元数据通信复杂度，该原语在一步广播中具有线性通信复杂度。基于T-RBC，Fides重新定义了DAG构建规则，将连续顶点之间的引用需求从2f+1降低到f+1。这种新结构削弱了DAG的连通性，并使传统提交规则失效，因此我们正式抽象了该问题，并推导出新的活性理论界限。我们进一步提出了一种四轮提交规则，实现了理论上的最小提交延迟。此外，我们设计了两个额外原语T-RoundCert和T-Coin，以高效认证DAG引用并替代先前协议中昂贵的密码学公共硬币。在跨地域和本地测试平台上的全面评估表明，Fides在保持强安全性和活性保证的同时，在延迟和吞吐量方面显著优于现有协议，包括Tusk、Bullshark、Mysticeti、RCC、Damysus、Achilles和HybridSet。
英文摘要：
DAG-based BFT consensus has attracted growing interest in distributed data management systems for consistent replication in untrusted settings due to its high throughput and resilience to asynchrony. However, existing protocols still suffer from high communication overhead and long commit latency. In parallel, introducing minimal hardware trust has proven effective in reducing the complexity of BFT consensus. Inspired by these works, we present Fides, an asynchronous DAG-based BFT consensus protocol that, to our knowledge, is among the first to leverage TEEs to enhance both scalability and efficiency. Fides tolerates a minority of Byzantine replicas and achieves $O(κn^2 + n^3)$ metadata communication complexity through a customized TEE-assisted Reliable Broadcast (T-RBC) primitive with linear communication complexity in one-step broadcast. Building on T-RBC, Fides redefines the DAG construction rules by reducing the reference requirement from $2f+1$ to $f+1$ between consecutive vertices. This new structure weakens DAG connectivity and invalidates traditional commit rules, so we formally abstract the problem and derive new theoretical bounds of liveness. We further propose a four-round commit rule that achieves the theoretically minimal commit latency. Besides, we design two additional primitives, T-RoundCert and T-Coin, to efficiently certify DAG references and replace the costly cryptographic common coin used in prior protocols. Comprehensive evaluations on geo-distributed and local testbeds show that Fides substantially outperforms state-of-the-art protocols, including Tusk, Bullshark, Mysticeti, RCC, Damysus, Achilles and HybridSet, achieving lower latency and higher throughput while preserving strong safety and liveness guarantees.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
