4.4 Mobile Modem

Monitor status and configure APN and Protocol on the Mobile interface.

1 Status

After accessing the router admin panel, you can find the "DEVICE" section on the right side of the front page. It includes most of the SIM card and mobile modem working status. Click the "Reacquire" button to update the mobile connection status.

  • Mobile Modem is the model of 4G LTE modem.

  • IMEI Number, a short of International Mobile Equipment Identity number. It's a unique serial number of the mobile modem.

  • SIM Card is the current SIM slot that has been activated.

  • SIM Status is the working status of the inserted SIM card. If it shows "Connected," we can then ignore the APN and protocol settings on the below steps.

    If the "SIM status" shows an error, please refer to below step 4.4.5 to run debugging.

  • Mobile Operator is the provider of wireless communications services. *Usually the same as the SIM card provider.

  • Global Cell ID is a globally unique identifier of the current cell tower connecting to.

  • Signal Strength is the general grade of the received signal quality. RSRP: The average power received from a single reference signal. RSRQ: Indicates the quality of the received signal. RSSI: Represents the entire received power, especially for 2G 3G networks. SNR: The signal-to-noise ratio of the given signal.

2 Mobile Interface

Go to "Network > Interfaces" to visit the interface overview page. Locate the "Mobile" interface and check the 4G internet IP address and traffic flow.

You can manually "Stop" or "Restart" the Mobile modem on the interface overview page.

Do not click the "Delete" button to erase any of the interfaces.

3 APN Settings

APN, short of Access Point Name, is the gateway to access the mobile network. In general conditions, the EZR33L router can use the default APN parameters prebuilt in the cellular modem to set up a connection.

Some of the mobile carriers use different APN parameters for the various data plans. You can configure the APN settings on the mobile interface to adapt to mobile carrier's networks.

  1. Access the router admin, go to "Network > Interfaces."

  2. Click the "Edit" button on the row of the "Mobile" interface.

  3. Click the tab of "Primary SIM1". If using the SIM2 slot, edit on the tab of "Secondary SIM2". APN: Input the mobile carrier's APN gateway address. PIN: 4-digit code. If you have not changed it before, leave it empty. PAP/CHAP Username: Username of the APN gateway. PAP/CHAP-Password: Password of the APN gateway. Authentication Type: Leave it as "--Please choose--" or choose PAP in most cases. IP Connection Type: Leave it as "--Please choose--" or choose IPv4 in most cases. Forbid Roaming: Leave it unselected unless you need to disable the roaming function.

  4. Click the "Save & Apply" button on the bottom right corner to apply the new settings.

  5. It will jump back to the interface overview page, wait 1-2 minutes until the mobile modem reconnects to the mobile network.

  6. If Mobile can not connect, please reboot the router.


Below are the examples of APN parameters. You can contact with mobile carrier's customer service to acquire the specific APN parameters of your data plan.

Here are the internet APN settings for some of the UK mobile phone operators.


APN Gateway









3 Three


<Not set>

<Not set>








internet (or) wap.vodafone.co.uk




4 Mobile Protocols

Some of the carriers or data plans might not support the default Mobile-Data protocol based on the QMI protocol. For example, in UK rural areas, the EE and Vodafone can only use the PPP protocol. In this case, please follow the below steps to switch protocol to 4G-PPP.

4G-PPP, a short of the point-to-point protocol. It is a traditional data link layer communications protocol. PPP protocol has been very widely used and most flexible for interoperability with devices.

Switch to 4G-PPP

After accessing the router admin, go to "Network > Interfaces." Click the "Edit" button on the "Mobile" interface.

  1. Under the "Common Configuration > tab of General Setup," choose "4G-PPP" on the field of "Protocol."

  2. Click the confirm button "Switch protocol." It will jump to the 4G-PPP protocol setup page.

  3. On the refreshed tab of "General Setup," you can use the default settings in most cases. Protocol: Now is using "4G-PPP". Modem device: Should use the device of "/dev/ttyUSB2". Active SIM Card: Use "Primary SIM1" if the SIM card inserted in the SIM1 slot Auto Switch SIM card: Leave it unactivated unless you need to switch between two SIM cards.

  4. Click the tab of "Primary SIM1" to edit APN settings. Refer to above step 4.3.3. Service Type: Choose UMTS/GPRS for UK/Europe/Asia/Africa. Choose CDMA/EVDO for the USA and Canada. Dial number: Use *99# for UK/Europe/Asia/Africa. Use *99***1# for the USA and Canada.

  5. Click the "Save & Apply" button to apply the new protocol and APN settings.

  6. It will jump back to the interface overview page, wait 1-2 minutes until the mobile modem reconnects to the mobile network.

  7. If Mobile can not connect, please reboot the router.

5 Debug

If getting an error on the above step 4.4.1 and 4.4.2 and has no internet connection, please verify if have a strong enough signal in your area (refer to step 2.2).

If the same SIM card works well on another modem or phone, please confirm it's unlocked, turn off the power and re-insert the SIM card.

SIM status on the frontpage

Possible reason and related operation


Please verify the LTE signal strength and re-check the SIM card installation.

Connection attempt failed

Turn off the power and re-insert the SIM card.

Verify if the data plan supports use on a 4G router.

The network device is not present.

The guardian module is resetting the modem. Wait for 2~3 minutes until the modem boot up.

Connected, but no internet.

Do not set up an "IPv4 gateway" on the LAN interface. It usually happens on locked SIM cards. Verify the PIN code and check with the carrier about the data plan.

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