I tried to establish communication between two PCs over 2 routers (1PC --> 1R <--> 2R <-- 2PC). Routers have SIM cards and they are on the same network (10.3.7.0). I have OPCUA client on PC2 and I need to read data from 1PC where is OPCUA server. My idea is to create port forwarding from 1PC through the 1R and 2R but I'm not sure how to configured port forwarding.
PC1 - IP Address: 192.168.20.2, Default Gateway: 192.168.20.20
Router1 - WAN IP Address: 10.3.7.181, LAN IP Address: 192.168.20.20
Router2 - WAN IP Address: 10.3.7.165, LAN IP Address: 192.168.1.1
PC2 - IP Address: 192.168.1.20, Default Gateway: 192.168.1.1
1. Can someone explain to me what is Source IP, Destination IP and Internal IP in port configuration?
2. What is the easiest way to solve this problem? I tried using PPTP, L2TP, Static Routing and Port Forwarding but unsuccessfully.