History – How did peer discovery work in Bitcoin v0.1?

In addition to learning and sharing their own addresses, nodes also learned about other node addresses through IRC channels. See irc.cpp.

After the node learns its own address, it encodes its address into a string and uses it as an alias. We then randomly joined an IRC channel named between #bitcoin00 and #bitcoin99. Then came the WHO order. The thread read the lines appearing in the channel and decoded the IP addresses of other nodes in the channel. We did this over and over again forever, until the node terminated.

When the client discovered the address on IRC, it set the timestamp of the address to the current time, but with a “penalty” of 51 minutes. That said, it actually seemed like I saw it almost an hour ago.