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Like name implies is simply that, a modem to supply internet connection to already existing devices. Imagine USB stick modem just for industrial purposes with rugged housing that can be controlled through AT commands and provides wide range of connectivity options like 2G (EGPRS) to 4G LTE Cat 1, LTE Cat-M1 and NB-IoT.
TRB Gateways
Much more functional than TRM modems, on top of simply providing internet connection, they can be controlled through RMS (Remote Management System) Depending on model they feature serial ports (RS485 and RS232) to connect to industrial devices, Inputs/Outputs, to connect sensors and device control, or RJ45 Ethernet port. They have GUI to connect, control and configure through browser and can establish VPN services for secure remote connection, Modbus, MQTT and other protocol for device control and data transfer.
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