Eth2.0-NA: Modeling Message Propagation to Optimize Mesh Size in Ethereum 2.0 Network

Ethereum 2.0 adopts a new publish/subscribe-based network protocol stack to support its peer-to-peer (P2P) architecture for exchanging consensus messages under the Proof-of-Stake mechanism. Each node scores its peers based on historical behavior and maintains a mesh set of high-scoring peers that can receive and forward full messages. As a result, message propagation time and bandwidth consumption are highly sensitive to the mesh set size. Despite its critical role, optimizing the mesh size to balance propagation delay and bandwidth cost has received limited attention. To fill this gap, we propose the Ethereum 2.0 Network Analyzer (Eth2.0-NA), a framework that optimizes mesh size through two key contributions: (1) a theoretical model that quantifies the relationship between message propagation hop count and mesh size, enabling mesh size optimization for a given hop count target; and (2) a distributed measurement architecture employing multiple probe nodes to empirically validate the model. Experimental results confirm that the theoretical model aligns closely with real-world network behavior. Leveraging this model, we recommend reducing the default mesh size from 8 to 7 on the Ethereum 2.0 MainNet, achieving a 14.1% reduction in bandwidth consumption without increasing propagation delay.