Hello,
I’ll go over each of the modes and explain a little about all of them:
-
NAT mode
This is the most commonly used mode - it handles L3 routing, as well as NAT (Network Address Translation). In this mode, managed Teltonika products can support more than one LAN client, by providing each of them with a private IP address. If you have a public IP address on your mobile interface, port forwarding can be configured to forward specific ports to LAN clients. Some people also treat NAT as another layer of security, as without manually opening the ports from the public internet, LAN clients will not be reachable. -
Passthrough mode
In this mode the router shares the IP address assigned by the operator with a single LAN clients. Great option in cases where the router needs to have internet access itself (for example RMS, ping reboot, monitoring, etc.). -
Bridge mode
The router forwards the DHCP lease from the carrier directly to the LAN client. This way the router/gateway will only act as a “bridge” between the LTE network and a wired client.
It should also be noted that in Passthrough and bridge modes the device will not be reachable. In order to reach the WebUI you’ll need to set a static IP address of the router LAN network.
More information can be found here: RUTX11 Interfaces - Teltonika Networks Wiki
Hope this helps!
Best regards,