Cellular modems for SMS Notification


TopView provides support for both serial/USB and network cellular modems/devices for SMS. If you do not currently have a cellular modem/device we recommend implementing a networked cellular modem/device.

Connecting to a cellular network requires a plan with a cellular carrier that supports the chosen cellular modem (GSM/CDMA/HSPA). This plan will give you a SIM card to insert into the cellular modem, giving the device a cellular phone number. If the cellular plan includes SMS/text messaging (required), TopView can then use this cellular device to send/receive SMS text messages to/from cellular phones.

You must select a cellular modem/device that supports the frequency band(s) of your country and carrier.

A network cellular modem/device is connected to the same network as TopView. The cellular device has an IP address on the network and TopView communicates to the cellular device over the network. There are no drivers required on the TopView machine.

Yeastar TG200 Series VOIP GSM Gateway

TopView v6.37 and later supports the Yeastar TG series for outgoing and incoming SMS. This is a GSM device that also allows users to make VOIP phone calls over cellular. Verizon SIMs are not supported with this device.

Please read our Yeastar TG200L configuration document for details on purchasing the correct model and configuring this Yeastar device for SMS and VOIP.

MultiTech rCell 100 cellular modem

Using network cellular modems in TopView requires a MultiTech cellular modem that supports their HTTP/HTTPS API used by TopView.

We recommend the MultiConnect rCell 100 series modems. They are available for GSM, CDMA (Verizon), and LTE (all carriers) and support the bands of most countries.  In addition these modems support the MultiTech HTTP/HTTPS API used by TopView.  Please contact MultiTech sales if you have any questions about the correct rCell 100 modem for your country and carrier.

In the United States we are using the following rCell 100 modems for development and testing:

Current models:

  • MTR-LNA7-B07 and MTR-LNA7-B07-US LTE (GSM and Verizon):
    • GSM: supported in TopView 6.33 and later
    • Verizon:
      • Outgoing SMS: supported in TopView 6.33
      • Incoming SMS (alarm acknowledge):
        Not supported with firmware 5.1.x
        Supported with firmware 5.2.1 and TopView 6.34

The MultiTech rCell modems have a web-based configuration utility. Please follow our MultiTech rCell 100 Configuration document to assist with the modem configuration steps.

Where to buy the MTR-LNA7-B07

Previous models:

  • MTR-LAT1-B07-US GSM (AT&T, T-Mobile, and compatible)
  • MTR-LVW2-B07-US CDMA (Verizon). See note below regarding SIM cards for this model

SIM cards for Verizon (older MultiTech devices)

With older modem firmware (before 5.2.1), TopView only supports incoming SMS messages if the SIM supports SMS storage. Most SIM cards from Verizon do not allow the modem to store SMS messages on the SIM.

Therefore we recommend users install firmware 5.2.1 or later.

Firmware 5.2.1 was released in May, 2020. This firmware allows incoming SMS messages for Verizon SIMS regardless of their ability to store messages on the SIM.

Firmware 5.1.x and earlier:

The SIM card you use must allow the modem to store incoming messages on the SIM card. Some Verizon SIM cards issued since Q1 2017 may not allow storage of messages to the SIM card. More information about this issue is available from MultiTech

We have tested and confirmed that the following SIM card SKUs will work with the MTR-LVW2-B07-US Verizon modems for incoming SMS.


A SIM card can be ordered from Verizon or 3rd party retailers. Obtaining the correct SIM cards through Verizon may be challenging so we offer the following additional options:

  • TopView evaluation customers and current customers with active support can obtain the correct SIM card through Exele. Please contact Exele Support for more information.
  • For direct purchase of the M2MTRI-NONRUG-GD-D cards you can set up an account with Ice Mobility, a 3rd party Verizon re-seller. The part number for the SIM card is PN024271.

Please contact Exele Support with any questions about SIM cards.

TopView network cellular modem feature details

  • Support for LTE, HSPA, and others
  • Virtual machine friendly
  • No modem drivers to install on the TopView computer
  • A single network cellular modem/device can be used by multiple TopView Engines for both outgoing SMS notification, incoming acknowledge, and incoming information request.
  • For MultiTech cellular modems, the network communication between TopView and the cellular modem is via HTTP or HTTPS so you can have a secure HTTPS communication channel if desired. HTTPS will require that you install a certificate on the TopView machine. HTTPS configuration details are located in our configuration document referenced above.

Note: Major carriers in the US are migrating from CDMA and GSM to LTE

Wireless carriers are deprecating 2G and 3G and will be moving to LTE. Both Verizon and AT&T (previously GSM) will move to LTE. This will happen over a long period of time, culminating in 2022.

More resources:

USB/Serial cellular modem (GSM)

A USB/serial modem connects to the TopView computer through a USB or serial port. We recommend implementing a networked cellular modem instead of a USB/Serial cellular modem.

There are many USB/serial GSM cellular modems on the market and most will work with TopView. For operation with TopView the modem should be ETSI 07.05 compliant and support sending and receiving of SMS in PDU mode

We suggest using MultiTech MultiConnect® Cell 100 Series cellular modems for SMS notification in TopView. The available models support the bands available in most countries. In our office (United States), we use the following USB GSM modem with TopView:

  • MTC-H5-B03-KIT (3G Cellular Modem)
    This is a 3G modem with USB power/connection to the TopView computer. Recommended for United States customers.
    More information…

TopView USB/Serial cellular modem feature details

  • Support for GSM only
  • Not virtual machine friendly
  • Modem drivers must be installed on the TopView computer
  • A single cellular modem can be used by multiple TopView Engines for outgoing SMS notifcation (with proper retry configuration) but cannot be used for incoming acknowledge of multiple TopView Engines.
  • Incoming messages to request current information (“SMS information request”) is supported for a single TopView Engine.

InstallationDownload and install the latest drivers from MultiTech, then plug the USB modem into the computer.

Where to buyMultiTech: www.multitech.com and distributors ( www.cdw.com and others)