The server is used for hole punching, to open up a P2P connection thorugh NATs and Firewalls. If it doesn’t work the server also relays the traffic between the clients.
Getting an end to end connection through todays internet is unfortunately not easy for an average user.
But why do you need a server for such a program? Can’t it be P2P or with the server stuff running on the client machine?
The server is used for hole punching, to open up a P2P connection thorugh NATs and Firewalls. If it doesn’t work the server also relays the traffic between the clients.
Getting an end to end connection through todays internet is unfortunately not easy for an average user.