If your device is connected to WiFi you can enable it to forward packets along to an MQTT server. This allows users on the local mesh to communicate with users on the internet.
MQTT Server username to use (most useful for a custom MQTT server). If using a custom server, this will be honored even if empty. If using the default public server, this will only be honored if set, otherwise the device will use the default username.
MQTT password to use (most useful for a custom MQTT server). If using a custom server, this will be honored even if empty. If using the default server, this will only be honored if set, otherwise the device will use the default password
Whether to send encrypted or decrypted packets to MQTT. This parameter is only honored if you also set server (the default official mqtt.meshtastic.org server can handle encrypted packets) Decrypted packets may be useful for external systems that want to consume meshtastic packets.
Enable the sending / consumption of JSON packets on MQTT. These packets are not encrypted, but offer an easy way to integrate with systems that can read JSON.