They allow to publish the data received from Ethernet (TCP/UDP messages) into a MQTT
Server.
These gateways allow a fast and easy access to the IoT world and they are compatible with IoT Servers ( Microsoft Azure, Amazon AWS, IBM Cloud, Google Cloud... etc and customized Servers) that support MQTT.
The MQTT communication can be encrypted using TLS / SSL protocols, ensuring a SECURE and
SAFE communication.
The Ethernet messages and the commands to send will be completely configurable and it will be
possible to interface with all the Ethernet Devices/Softwares based on custom Ethernet
protocols.
For informations about Serial / MQTT converters switch
here