Interfacing LoraWAN with MQTT

The advent of IoT and the explosion in the number of devices that can potentially be connected to the Internet, has led to LoraWAN changing the way that systems and devices can be connected together.

With the advent of IoT, it has become possible to seamlessly connect gateways, servers, devices and their users at all times.  However, two broad concerns arise: LoRaWAN topology assumes the availability of a LoRa gateway to convert LoRa messages into UDP and http frames and feed them to a LoRa server, and from there to application servers in the cloud.  This poses the first concern: in an outdoors environment, Internet access may not always be present; hence a permanent cloud connection may not always be available.  Therefore, in order to be able to monitor in real time, devices that are connected remotely, it will be necessary to rely on local edge analytics servers for private local networks.  The second concern being security, LoRa must then provide the MQTT messaging protocol over TCP/IP to enable message dispatch to users that require data.  Hence, the need for LoRa MQTT.

RAK’s iTracker NRF52 module can be configured to run an MQTT client to an MQTT broker via IPv6.  LoRaWAN is a low power, wide area network (LPWAN) meant for connecting devices so as to allow long range communications at a low bit rate.  In this, the long range physical layer radio is provided by LoRa and is especially for devices that are batter-operated and with low-power sensors.  Therefore LoRa devices are very easy to install, requiring no direct wiring (as they are battery-operated), and hence cost of installation is very low.

It is to be noted that MQTT authentication and authorization are two aspects that are not typically handled by the LoRa server.  The MQTT broker will need to take on this responsibility and ensure that proper authentication and authorization is done in order to restrict gateways and applications so that they can only publish and subscribe to their own MQTT topics.

Over the past few years the digital revolution in the form of IoT has completely transformed the way we use devices connected to the Internet.  LoRa MQTT, by combining the benefits of LoRaWAN technology and the small-code footprint of MQTT, is able to help manufacturers envisage what device communication of the future is going to look like.