ETHNetPRecover: Ethereum Network Topology Recovering via Passive Transaction Monitoring

Ethereum is a decentralized blockchain system that relies on a peer-to-peer (P2P) network. Understanding the topology of this P2P network is crucial for assessing the security, reliability, and user anonymity of Ethereum (ETH). However, the routing table of Ethereum network nodes is private and inaccessible, making the Ethereum network topology hidden. Safeguarding the topology is essential to protecting Ethereum's privacy and security. Therefore, attempting to measure the entire ETH network's topology is a crucial foundation. This paper proposes a completely passive method called ETHNetPRecover, which only requires monitoring transactions to recover the entire ETH network's topology. This method can determine the presence of an edge between two nodes with 96.8% precision. We compared our method's performance with similar approaches and found it recovers the Ethereum network topology faster without additional transaction costs. Using the recovered topology, we tracked and marked transaction entry nodes in the Ethereum Mainnet over seven days. We discovered that 93% of the transactions during this period entered the Ethereum Mainnet network through 30 entry nodes. Through our evaluation, we found that our method has high precision, is efficient, and incurs no additional costs, making it a relatively effective approach.