We have a measurement campaign in a field, until now we had the following network structure
The distance was 400m between the two points so the most easy solution was to use a Wifi pont to point bridge connection. The PC with the 192.168.0.10 IP act as a server, and run a software which controls the other PC. In this network structure all PC had the same subnet and it was easy to establish TCP/UDP(Broadcasting, unicasting) connections.
From now on the distance between the two point is 20km, so the wifi solution is not working any more. In this case we have the following network structure:
My question is how can I establish a point to point connection through internet, to get the same structure as in the first image? For example where I still can broadcast and unicast through UDP etc.
Edited
I know only the VPN server IP, so from the PC with the 13x.xxx.xxx.xxx IP can connect to the VPN server, therefore that PC will be in the same subnet(192.168.1.0/24). For example, there will be eth0 with 13x.xxx.xxx.xxx IP and tun0 with 192.168.1.22, in this case can I run a VPNServer on that PC so the PC with the 192.168.1.21 IP can establish a VPN Bridge connection?
You should get site 2 a permanent, reliable internet connection and use a permanent site to site VPN. You'll need a router each side capable of doing so, though.