I am planning a new large site that does not have wired infrastructure.
At one end, there will be a main SCADA cabinet with a PLC inside. At the other end, there will be Ethernet-based devices that need to be on the same network as the SCADA system.
I plan to use RUT241 devices at both ends. What configuration should be applied to allow the two RUT241 units (or possibly more units) to communicate with each other as if they were on the same LAN? I need to enable ping and full network communication between both sides, there will be SIM or local WAN at each end.
Thank you for your question regarding your new site setup.
A VPN between your two RUT241 routers is the right approach and will be sufficient for your use case. Here’s a quick summary of what we recommend:
Recommended Setup: Routed VPN (WireGuard or OpenVPN)
Both are natively supported on the RUT241. This creates a secure tunnel between the two sites, allowing full IP-level communication - including ping, Modbus TCP, and most industrial protocols used with SCADA/PLC systems.
Key Configuration Points:
Assign a distinct subnet to each site (e.g., 192.168.1.0/24 on the SCADA side, 192.168.2.0/24 on the remote side).
Configure static routes on both routers so traffic is forwarded correctly through the tunnel.
For more than two sites, a hub-and-spoke VPN topology will scale cleanly.
Important Note for SIM/Cellular Connections:
Mobile operators often assign private (CG-NAT) IP addresses to SIM cards, which prevents a RUT241 from acting as a VPN server directly. To work around this, you can either use a cloud/VPS server as a VPN hub, or leverage Teltonika’s built-in RMS VPN feature, which handles this automatically with minimal configuration.
Do you need Layer 2 bridging?
If your devices rely on broadcast traffic or must be on the exact same subnet, a bridged (Layer 2) VPN can be configured — however, for standard SCADA/PLC communication, the routed setup above is recommended as it is simpler and more stable over cellular.
Please feel free to reach out if you need help with the specific configuration steps.