Conclusiones y discusión

In this thesis, we measure the Ethereum’s peer-to-peer (P2P) network to provide a better understanding of the previously unexplored network. Using the Ethereum’s net- working protocols, we find nodes and collect their information. Based on the data collected over a five-month period, we examine the DEVp2p network, the underlying P2P network of Ethereum. We identify publicly-reachable Ethereum Mainnet nodes and maintain at least 2k peer connections. We analyze the peers and information propagation on the network. We compare the network’s properties to those of other P2P networks.

We find that the DEVp2p network is a highly diverse environment shared by multiple services, and the Ethereum Mainnet makes up only 12% of the network. We observe that almost half of disconnects experienced by our Mainnet nodes were caused by non-Mainnet or non-Ethereum nodes. Second, the peer connections on the Mainnet is formed in an unstructured way and exhibit much lower level of churn compared to those on the Gnutella network. Lastly, from our transaction analysis, we find that there exist a large volume of old transactions—no longer useful to the network—that continue to be propagated by peers with outdated blockchain.

Due to lack of time, many experiments and analysis have been left for the future. The next step to follow this work is to infer the Mainnet’s topology through a further analysis of transaction and block propagation and to identify fundamental network properties, such as node connectivity. The inferred topology and the findings in this work could be used to examine whether cryptocurrencies in general exhibit properties similar to the ones seen in the Ethereum Mainnet. Another interesting area to investigate is classification of unordinary nodes—such as those with outdated blockchain—and measuring their impact on the network stability.

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