Connecting to Peers

Connecting to a peer is done by sending a version message, which contains your version number, block, and current time to the remote node. The remote node responds with its own version message. Then both nodes send a verack message to the other node to indicate the connection has been established.

Once connected, the client can send to the remote node getaddr and addr messages to gather additional peers.

In order to maintain a connection with a peer, nodes by default will send a ping message to peers every 2 minutes. If no data is sent to a peer for 20 minutes, no data is received from it for 20 minutes, or a ping message goes unanswered for 20 minutes, the client will assume that connection has closed. A peer is also disconnected if its send buffer stays full (sending paused) for 20 minutes.