Dedicated server app that can be run at linux server.

[AdamN]

The dedicated server is probably just the adhoc server, you can find it's source code somewhere in this forum, bur probably easier to find at github.

However, if you're planning to run your own adhoc server on the internet, players playing on your server will be the same as using any other public adhoc server (ie. socom.cc), whether those players will need virtual LAN (ie. VPN) or not depends whether those players can do port-forwarding or not (with VPN you don't need port-forwarding)