Byzantine Consensus is fundamental for building consistent and fault-tolerant distributed systems. In traditional quorum-based consensus protocols, quorums are defined using globally known assumptions shared among all participants. Motivated by decentralized applications on open networks, the Stellar blockchain relaxes these global assumptions by allowing each participant to define its quorums using local information. A similar model called Consensus with Unknown Participants (CUP) studies the minimal knowledge required to solve consensus in ad-hoc networks where each participant knows only a subset of other participants of the system. We prove that Stellar cannot solve consensus using the initial knowledge provided to participants in the CUP model, even though CUP can. We propose an oracle called sink detector that augments this knowledge, enabling Stellar participants to solve consensus.

翻译：拜占庭共识是构建一致且容错分布式系统的基础。在传统的基于法定人数的共识协议中，法定人数通过所有参与者共享的全局已知假设来定义。受开放网络去中心化应用的推动，恒星区块链通过允许每个参与者利用本地信息定义其法定人数，放宽了这些全局假设。一种名为“未知参与者共识”（CUP）的类似模型，研究了在参与者仅知晓系统部分其他参与者的自组网中解决共识所需的最小知识。我们证明，即使CUP能够解决共识，恒星协议利用CUP模型提供给参与者的初始知识也无法解决共识。我们提出一种名为“接收器检测器”的预言机，用于增强这一知识，使恒星协议参与者能够解决共识。