ESP32 is a well known WiFi integrated SoC. The SIM7600EI is a 4G/GSM/GPRS/GPS UART modem.
The SIM7600 GSM Modem is having MQTT stack builtin. This enables us to use simple AT commands to connect to an MQTT broker and publish messages. The MQTT topics can also be subscribed for receiving messages from other MQTT client.
(to be updated)