The Bitcoin P2P Network.

The Bitcoin virtual currency is built on the top of a decentralized peer-to-peer (P2P) network used to propagate system information such as transactions or blockchain updates. In this paper, we have performed a data collection process identifying more than 872000 different Bitcoin nodes. This data allows us to present information on the size of the Bitcoin P2P network, the node geographic distribution, the network stability in terms of interrupted availability of nodes, as well as some data regarding the propagation time of the transmitted information. Furthermore, although not every Bitcoin user can be identified as a P2P network node, measurements of the P2P network can be considered as a lower bound for Bitcoin usage, and they provide interesting results on the adoption of such virtual currency.