Node discovery (mainly same with bitcoin, for blockchain project)
On the current NAT forwarding network environment, whether it is self-discovery or the discovery behavior of the other party is not completely accurate, it is certain that the address received by the user is not 100% available.
There are two actions in this protocol:
When the connection is established, the requester(Client) will actively request the responder(Server) to request the list of available addresses that the responder has stored. WARNING: This behavior is only allowed once, otherwise it will be disconnected by the other peers.
Each node periodically broadcasts hot address to its neighbor peers. The hot address refers to the listen address of the neighbor peers that the node keeps communicating continuously, which means active connection.
``` /// request for address list GetNodes { version: Uint32, count: Uint32, listen_port: PortOpt, }
/// response address list Nodes { announce: Bool, items: NodeVec, } ```