Understanding Router Mode vs. Bridge Mode (IP Passthrough) on Zyxel FWA Series Devices

Zyxel FWA 5G routers such as FWA710, FWA510, and FWA505 support both Router Mode and Bridge Mode (IP Passthrough). This guide explains the key differences between the two modes, when to use each, and how to configure them properly. Whether you're setting up a simple home network or integrating with a business-grade router or firewall, understanding these modes ensures optimal performance, secure connectivity, and the flexibility to meet different networking needs.

What is Router Mode?

In Router Mode, the Zyxel FWA device acts as a full-fledged router:

• It obtains a public IP address from your Internet Service Provider (ISP) via the cellular network.
• It creates a private Local Area Network (LAN) and assigns IP addresses to connected devices using DHCP.
• It performs Network Address Translation (NAT), firewall protection, and traffic management.

Advantages of Router Mode:

• Simplified setup for home users.
• Built-in security features like NAT and firewall.
• No need for additional networking equipment.community.zyxel.com

2. What is Bridge Mode (IP Passthrough)?

Bridge Mode, also referred to as IP Passthrough, disables the routing functions of the Zyxel FWA device, allowing it to pass the public IP address directly to another device, such as a firewall or a more advanced router.

Key Characteristics:

• The Zyxel device becomes transparent to the network.
• The public IP address is assigned directly to the connected client device via the LAN interface.
• Routing functions like NAT, DHCP, and firewall are disabled.

Advantages of Bridge Mode:

• Ideal for business environments requiring advanced network configurations.
• Eliminates double NAT issues, which can affect VPNs and VoIP services.
• Allows the use of specialized external networking equipment.spdl.zyxel.com

Compatibility of Bridge Mode / IP Passthrough in Zyxel FWA Devices

How to Enable IP Passthrough on Zyxel FWA Devices

To configure IP Passthrough, follow these steps:

1. Access the web interface of your Zyxel device.
2. Navigate to:manualsnet.com

   Network Setting > Broadband > Cellular > IP Passthrough
   

3. Enable IP Passthrough.
4. Choose the mode:
   • Passthrough Mode: Enable
   • Passthrough Type: DHCP (default) or Manual, depending on your setup.
5. Select the interface (e.g., LAN1) to which the public IP will be assigned.
6. Apply the changes and reboot the device.support.zyxel.eu

Note: Some ISPs may use Carrier-Grade NAT (CGNAT), which can prevent the assignment of a public IP address to your device.

Comparison Table: Router Mode vs. Bridge Mode (IP Passthrough)

When to Use Each Mode?

Use Router Mode if:

• You do not have an external router or firewall.
• You prefer a straightforward, all-in-one networking solution.
• You require basic network security features without complex configurations.

Use Bridge Mode / IP Passthrough if:

• You have advanced networking equipment, such as a dedicated firewall or router.
• You need to assign the public IP address directly to another device.
• You want to avoid double NAT issues, which can interfere with certain applications.

MGMT Services

There will be two Mgmt Services Tabs on the Device GUI.
"MGMT Services" is being used if the device is in "WAN Routing Mode", and "MGMT Services for IP Passthrough" will be used if the device is in "IPPT Mode".