Node count metrics on 21.ninja
Today, I added two more metric categories to 21.ninja:
The first category is probably not that interesting, given that other sources [1, 2, 3] already provide a subset of similar data.
The unique node category, however, should be new. The category’s rationale is to attempt to accounts for the fact that Bitcoin nodes can connect to the P2P network via multiple network types, and that naively interpreting each reachable addresses as a node leads to an overestimation of the actual number of nodes. Consider, for example, a single node which connects to the network via IPv4, IPv6, and Tor, in this way contributing three distinct reachable addresses. In regular reachable nodes data, this single node will be counted as three nodes. In the unique reachable nodes metric, however, the node is correctly identified as a single node. If you’re interested in how this done, check out the methodology for the unique reachable node metric.
The figure below compares reachable to unique reachable nodes, revealing a current overestimation bias of around 1.6x for naive reachable node count estimates.
Ack
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, thanks guys!