  A recent spam wave of IP addresses in the Bitcoin P2P network allowed us to
estimate the degree distribution of reachable peers in the network. The
resulting distribution shows that about every second reachable peer runs with
Bitcoin Core's default setting of a maximum of 125 concurrent connections and
nearly all connection slots are taken. We validate this result and, in
addition, use our observations of the spam wave to group addresses that belong
to the same peer. By doing this grouping, we improve on previous measurements
and show that simply counting addresses overestimates the number of reachable
peers by 13 %.
