This paper presents a study of the Poof-of-Stake (PoW) Ethereum consensus protocol, following the recent switch from Proof-of-Work (PoS) to Proof-of-Stake within Merge upgrade. The new protocol has resulted in reduced energy consumption and a shift in economic incentives, but it has also introduced new threat sources such as chain reorganizations and balancing attacks. Using a simple and flexible agent-based model, this study employs a time-continuous simulation algorithm to analyze the evolution of the blocktree and assess the impact of initial conditions on consensus quality. The model simulates validator node behavior and the information propagation throughout the peer-to-peer network of validators to analyze the resulting blockchain structure. Key variables in the model include the topology of the peer-to-peer network and average block and attestation latencies. Metrics to evaluate consensus quality are established, and means to observe the model's responsiveness to changes in parameters are provided. The simulations reveal a phase transition in which the system switches from a consensus state to a non-consensus state, with a theoretical justification presented for this observation.

翻译：本文针对以太坊共识协议在Merge升级后从工作量证明（PoW）转向权益证明（PoS）的现状展开研究。新协议虽降低了能耗并改变了经济激励模式，但也引入了链重组和平衡攻击等新型威胁源。本研究采用一种简洁灵活的基于智能体的建模方法，通过时间连续模拟算法分析区块树的演化过程，并评估初始条件对共识质量的影响。该模型通过模拟验证节点行为及其在点对点验证节点网络中的信息传播过程，解析由此产生的区块链结构特征。模型中关键变量包括点对点网络的拓扑结构以及平均区块与认证延迟时间。研究确立了共识质量的评估指标，并提供了观察模型对参数变化响应性的方法。模拟结果揭示了系统从共识状态向非共识状态转变的相变现象，本文对此观测结果给出了理论解释。