About Modem Interfaces

If your business operates in areas with weak ISP coverage, or you have non-traditional methods for Internet access, a dedicated modem interface can increase your network flexibility.

You can add one modem to a supported Firebox device. In Fireware v12.1 and higher, the modem is available as an external interface and appears in the list of Firebox interfaces.

About 4G LTE

On the Firebox T80, you can connect to a 4G LTE cellular network with an LTE interface module. This enables you to install a SIM card and use the cellular connection as an external interface on the Firebox for primary or backup WAN connectivity.

You cannot use a USB modem at the same time as the LTE interface module.

For information on how to configure the 4G LTE modem interface, see Configure a 4G LTE Modem.

Modems and Firebox Features

You can specify the modem interface when you configure these features:

The modem interface also appears in the Aliases list. You can add the modem interface to policies on your Firebox.

For mobile VPN connections to a modem interface that has a dynamic IP address, you must:

  • Register the modem interface with a dynamic DNS provider.
  • Configure dynamic DNS on the Firebox.
    For more information about dynamic DNS, see About the Dynamic DNS Service.
  • Specify the domain name for the modem interface in the mobile VPN settings

To configure a 3G/4G modem interface, see Configure a Modem Interface.

To configure a 4G LTE modem interface, see Configure a 4G LTE Modem.

Modems and Multi-WAN

You can configure a modem interface to participate in multi-WAN. By default, modem interfaces do not participate in multi-WAN. For information about multi-WAN methods, see About Multi-WAN Methods.

When you configure a modem interface as a multi-WAN participant, link monitor is not enabled for the modem by default to prevent unwanted bandwidth consumption. To configure the modem interface to monitor the default gateway or another source that you specify, you must enable link monitor. For more information about link monitor configuration, see About Link Monitor.

You can configure branch office VPN connections to fail over to the modem interface. For more information about VPN modem failover, see Configure VPN Modem Failover.

Multi-WAN is not supported on the Firebox T10, or XTM 2 Series devices without the Pro upgrade. Multi-WAN is supported on Firebox T15 devices with Fireware v12.3 or higher. Although multi-WAN is not supported in certain cases, modem failover is supported for the Firebox T10 and T15. This is true even after an upgrade to Fireware v12.1 or higher, which converts modems to external interfaces.

Modem Failover

If your Firebox is configured for modem failover, and you upgrade from Fireware v12.0.2 or lower to Fireware v12.1 or higher, the upgrade automatically converts the modem to an external interface with modem failover enabled. If all other external interfaces become unavailable, traffic automatically fails over to the modem interface.

For more information about modem failover, see Configure Modem Failover.

Supported Firebox and XTM Devices

These Firebox models support modems:

  • Firebox T Series: T10, T15, T20, T30, T35, T40, T50, T55, T70, T80, NV5
    (The Firebox T80 also supports the 4G LTE Modem interface module)
  • Firebox M Series: M200, M270, M290, M300, M370, M390, M400, M470, M500, M570, M590, M670, M690

USB dial-up modems are not supported.

Connect a serial or 3G/4G modem to a USB port on the Firebox:

  • To use a serial modem, you must have a dial-up account with an Internet Service Provider (ISP).
  • To use a 4G LTE or 3G/4G modem, the Firebox must use the minimum version of Fireware OS that supports the modem and you must have a 3G or 4G data plan with a wireless service provider.

Supported Modems

The 4G LTE interface module is currently supported only on the Firebox T80 with Fireware 12.7.1 and higher.

You can configure these 3G/4G modems on your Firebox:

Carrier 3G/4G USB Modem Vendor ID Product ID Fireware OS Requirement
N/A (UK and NL) D-Link DWM-221 0x2001 0x7e19 v11.10.7 or higher
N/A (UK and NL) D-Link DWM-2221 0x0BDB 0x1926 v12.0 or higher
AT&T Novatel Global Modem USB8003 0x1410 0xb024 v12.5.8 / v12.7.1 or higher
AT&T Netgear 340U2 0x1199 0x9051 v11.10.2 or higher
AT&T Sierra 313U 0x0f3d 0x68aa v11.7.4 or higher
AT&T Sierra Elevate 4G 0x1199 0x68a3 v11.8.3 Update 1 or higher
AT&T Netgear BEAM 0x1199 0x9051 v11.12.2 or higher
AT&T Velocity MF861 0x19d2 0x1405 v12.1 or higher
Bell (CA) Huawei E8372 0x12d1 0x14db v11.10.7 or higher
Deutsche Telekom Huawei E3372 0x12d1 0x1506 v11.10.7 or higher
Deutsche Telekom Huawei E3372 0x12d1 0x14dc v11.12 or higher
NTT / DoCoMo (Japan) NCXX UX302NC
0x11f6 0x1035 v12.2 or higher
NTT DoCoMo / au by KDDI / Softbank (Japan) Fuji Soft FS040U 0x1C9E 0xF133 v12.2 or higher
SFR (FR) Huawei E3372 0x12d1 0x14dc v11.12 or higher
Sprint Franklin U602 0x1fac Unknown v11.7.3 or higher
Sprint Sierra 250U N/A N/A v11.7.3 or higher
Sprint Franklin U301 N/A N/A v11.9.1 or higher
Sprint Netgear 341U 0x1199 0x9055 v11.8.3 or higher
Sprint Netgear 341U (revision) 0x1199 0x9057 v12.2 or higher
Sprint Franklin U772 0x1fac 0x0232 v11.12.2 or higher
Telcel (MX) Huawei E3372 0x12d1 0x14dc v11.12 or higher
Telus (CA) Netgear 340U2 0x1199 0x9051 v11.10.2 or higher
T-Mobile ZTE MF683 0x19d2 0x0157 v11.7.3 or higher
T-Mobile ZTE MF190 0x19d2 0x0117 v11.9.3 or higher
T-Mobile (NL) Huawei E3372-235 0x12d1 0x1506 v11.10.7 or higher
T-Mobile (NL) Huawei E3372-236 0x12d1 0x14dc v11.12 or higher
Telstra (ANZ) Huawei E8372 0x12d1 0x14db v11.10.7 or higher
Telstra (ANZ) Sierra 320U 0x0f3d 0x68aa v11.8.1 or higher
Verizon Pantech UML295 0x10a9 0x6064 v11.10.2 or higher
Verizon Novatel U620L 0x1410 0x9022 v11.10.5 or higher
Verizon Global Modem USB730L1 4 0x1410 0x9032 v12.1.1 or higher
Wind (Italy) Huawei E3372-320 USB 4G LTE 0x12d1 0x1f01
v12.7.2 or higher

1 The D-Link DWM-222 and Verizon Global Modem USB730L modems require more power than the USB port can supply on T10 or T15 Fireboxes. You may experience poor modem performance or frequent modem reboots. To use these modems with your Firebox, you can connect a powered USB hub to the Firebox and connect the modem to the hub. Other modem models might be affected.

2 To use the Netgear 340U with your Firebox, you might have to disable the Identity Morphing feature on the modem. For more information, see the Knowledge Base article NETGEAR AC340U modem not working with Firebox.

3 To use the AT&T USB800 Global Modem with your Firebox, you might have to change the local configuration on the modem. For more information, see the Knowledge Base article AT&T USB800 modem connects and disconnects from Firebox.

4 In some cases, your Firebox might fail to properly detect the USB730L modem, and the PID will appear as 0x9032 instead of the correct 0x9031. This indicates the modem is in a debug or diagnostic mode. To resolve this issue, follow these steps to revert the modem to Enterprise mode:

  1. Connect the USB730L to a client PC.
  2. With a web browser, connect to
  3. Under Device Mode, click Enterprise Mode.
  4. Wait about 2 minutes while the modem restarts. then click Save Changes to confirm the mode change.

Serial Modem Support

These serial modems are also supported:

  • Zoom FaxModem 56K model 2949
  • MultiTech 56K Data/Fax Modem International
  • OMRON ME5614D2 Fax/Data Modem
  • Hayes 56K V.90 serial fax modem

See Also

Configure a Modem Interface

Configure Modem Failover

Configure VPN Modem Failover