The MQTT protocol has taken great strength in recent years since it is simple, safe, practical and lightweight perfect for IoT and M2M applications.Thanks to the contribution of developers and developers of MQTT applications, there are public MQTT Broker for Internet monitoring and control tests, are available to connect from any MQTT client in this case we will use HIVEMQ, which has dashboard to view MQTT connections and Web sockets, since it is public should have some considerations that we will see below.” - Link