M5Stack Atom NB-IoT device with secure MQTT over IPv6(20 min read)

M5Stack produce a suite of pilot-suitable modular IoT devices, including the Atom DTU NB-IoT. The NB-IoT DTU (Narrow Band Internet of Things - data transmission unit) comes in a small 64 24 29mm case with a DIN rail clip on mounting and support for RS-485 including 9-24V power (or USB-C power).

The kit base has a SIM7020G modem and the ESP32-based Atom Lite (which also supports WiFi) is included with a very resonable price. The device has built in MQTT, supports secure public certificate TLS connections, and supports IPv6.

While the physical unit is ready for pilot deployment (and the M5Stack website has several commerical deployment case studies), there is no pre-written firmware for the device, so some up front development is needed.

As well as reviewing the strengths and weaknesses of the device, I will also provide some sample code for a proof-of-concept using an Env III environment sensor to transmit temperature, humidity, and air pressure to an MQTT test server using MQTTS (with server certificates), over IPv6, over NB-IoT.

M5Stack Atom DTU NB-IoT with Telstra SIM card

Continue reading M5Stack Atom NB-IoT device with secure MQTT over IPv6(20 min read)

Deployment ready NB-IoT device review — Unboxing the Dragino N95S31B(14 min read)

The Dragino NBSN95/NBSN95A family is a deployment-ready range of water resistant NB-IoT (Narrow Band Internet of Things) devices that are available pre-packaged with various sensors such as soil moisture, distance detection, liquid level, and temperature/humidity sensors.

NB-IoT is a Low-Power Wide-Area Network (LPWAN) technology that allows devices to be accessed in remote locations and operate on battery for long periods of time, up to many years.

In this article we will look a the N95S31B, the model with the pre-packaged temperature/humidity sensors, the strengths and weaknesses of the device, and then walk through configuing the device and see it connect to an MQTT test server. Our previous article showed you how to set up an MQTT test server on Azure if needed.

The NBSN95 is an open source project, with both the software and hardware specifications available, if you need to customise the application. We have also previously reviewed the Dragion LDDS75 LoRaWAN device.

Dragino wiring the serial connection

Continue reading Deployment ready NB-IoT device review — Unboxing the Dragino N95S31B(14 min read)

The end of 3G for IoT(10 min read)

3G (3rd generation mobile technology) networks for the major telecommunication companies are due to shut down over the next few years. This includes Telstra, whose network is now in the sunset phase and due to close in June 2024.

This will mean the end of 3G for Internet of Things deployments, and they will need to migrate to either LPWAN (Low-Power, Wide-Area Networks) or new generation cellular mobile, depending on the use case.

As pointed out in this article on Why you need to migrate your devices now! that does not give a lot of time. If you have 15,000 devices in the field you need to be replacing 30 devices per day — if you start tomorrow; more if you take long to commence your project.

The are three main options for migration, in two categories:

  • LPWAN
    • NB-IoT (Narrow-Band Internet-of-Things)
    • Cat-M1 (Category M1), also known as LTE-M (Long Term Evolution, Category M)
  • Cellular Mobile
    • 4G LTE (4th Generation) mobile

This post will explore those options in a bit more detail, as well as what other alternatives there might be. 5G NR (5th Generation New Radio) does not yet have wide enough coverage to be a viable option for IoT in most cases.

If this seems a bit overwhelming, given the short time frames and what you need to do, then you can also approach our consulting services, Telstra Purple, for advice and help.

Continue reading The end of 3G for IoT(10 min read)