UniFi Mobile Router Network Modes
UniFi Mobile Router Network Modes
The UniFi Mobile Router series supports three different network modes; Router Mode, LTE Passthrough Mode, and Ethernet Bridge Mode. Understanding these modes will help you configure your UMR, UMR-Industrial, or UMR-Ultra effectively for your specific networking needs.
Understanding UMR Network Modes
| Mode | Primary Use | IP Assignment | Recommended For |
| Router (Default) | Standard routing with full network features | UMR assigns private IPs | General users, failover scenarios |
| LTE Passthrough | Assigns public IP from ISP to a single device* |
ISP assigns public IP (1 device only)* |
Public IP for firewalls, VPN servers |
| Ethernet Bridge | Functions as a network bridge, no NAT, routing or LTE | Existing network assigns IP | Using UMR as a simple 2.4 GHz AP with no LTE capabilities at all |
*Assigns a public IP address to a single device—either the first connected device or a manually specified one. All other devices receive private IP addresses.
Feature Comparison by Mode
| Feature | Router Mode | LTE Passthrough | Ethernet Bridge |
| LTE | ✅ Yes | ✅ Yes | ❌ No |
| NAT | ✅ Yes | ✅ Yes* *Most devices use NAT, except where one device which receives IP directly from LTE carrier |
❌ No |
| DHCP Server | ✅ Yes | ✅ Yes | ❌ No |
| Firewall | ✅ Yes | ❌ No | ❌ No |
| VPN Support | ✅ Yes | ❌ No | ❌ No |
| Port Forwarding | ✅ Yes | ❌ No | ❌ No |
| Static Routes | ✅ Yes | ❌ No | ❌ No |
| Multi-WAN & Internet Failover | ✅ Yes | ❌ No | ❌ No |
| Public IP Assignment to Device | ❌ No | ✅ Yes (1 device only) | ❌ No |
| WiFi AP Mode | ✅ Yes | ✅ Yes | ✅ Yes |
Router Mode: Standard Routing with Full Features
When to Use Router Mode:
- When UMR is the primary or backup WAN source
- If firewall, VPN, and port forwarding features are needed
- When you require multiple WAN sources (Ethernet, WiFi as WAN, LTE/5G)
Features & Capabilities:
- Acts as a full-featured router with DHCP, firewall, VPN, and port forwarding
- Supports Multi-WAN failover and load balancing
- Provides NAT for network security
LTE Passthrough Mode: Assigns Public IP to a Device
In LTE Passthrough Mode, UMR hands off the mobile carrier's public IP to a single connected device via Ethernet or WiFi. This can be useful if UMR is providing internet to a downstream router (e.g., UniFi Cloud Gateway), or if you need a specific device in your network to have an individual public IP (such as a publicly-accessible server if your cellular network does not use CG-NAT).
When to Use LTE Passthrough Mode:
- If you are providing internet access to a downstream router, especially if that router needs to avoid double NAT (e.g., for VPN connectivity)
- If a specific device requires a public IP from the mobile network (e.g., firewall, VPN server, VoIP gateway)
Key Behaviors:
- The first connected or manually specified device (firewall, VPN appliance, or router) will receive the public IP assigned by the mobile operator
- UMR itself will not perform NAT or routing for that device
- Other devices connected to UMR will receive private IPs
Limitations:
- Firewall, VPN, Port Forwarding, Static Routes, and Internet Failover will be disabled
- Requires a special SIM card/subscription that provides a public, fixed IP from the ISP
- Only one device gets the public IP; other devices get private IPs
Custom IP Assignment Option:
- Users can manually assign a public IP to a specific device using its MAC address in the "Allocate IP to Device" setting.
- If disabled, the public IP will be assigned automatically to the first connected device.
Important:
- Do not create a DHCP static lease for the same MAC address that is assigned a public IP in LTE Passthrough Mode.
- DHCP static leases take precedence over LTE Passthrough assignments and may prevent the device from receiving a public IP.
Ethernet Bridge Mode: Pure WiFi Access Point Without Routing Functions
In Ethernet Bridge Mode, UMR functions as a switch or a 2.4G WiFi access point (LTE not enabled). It does not perform routing functions or assign IP addresses.
When to Use Ethernet Bridge Mode:
- When using UMR as a pure WiFi Access Point
Key Behavior:
- UMR will not act as a router or perform NAT
- No firewall, VPN, or routing capabilities
- UMR simply passes traffic between its WAN and LAN ports, and optionally to wireless clients
- Operates as a transparent bridge, allowing traffic to flow between devices without modification
- As long as the upstream router supports it, multiple devices can connect through UMR without limitations
Limitations:
- LTE is not employed at all
- Firewall, Port Forwarding, Static Routes, VPN, Multi-WAN, DHCP Server, and Internet Failover will be disabled
- UMR will no longer assign IP addresses; the existing network must handle DHCP
- Not intended for handing off a public IP; use LTE Passthrough instead
Conclusion & Best Practices
- Router Mode is the recommended default mode for most users, offering full networking features.
- LTE Passthrough Mode is ideal for assigning a public IP to a single device, such as a firewall or VPN appliance.
- Ethernet Bridge Mode is useful when UMR is simply acting as a switch or a 2.4 GHz WiFi access point in an existing network.
- Before switching modes, be aware that some features may be disabled.