Always-On, Keeping Cooler

There is a growing range of options when it comes to considering the type of connectivity best suited to your fleet of assets. It is very clear that the fastest-growing trend is to move away from connectivity types that require human intervention, towards “Always-On’ options.

What is Always-on?

In this context, Always-on is a term used to describe systems that are continuously connected to power sources and/or networks. These systems operate in the background, without the requirement for regular, in-person, intervention.

Why is this important for IoT devices?

Always-on is an invaluable solution for IoT devices, allowing for regular data uploads as well as immediate, one-off alerts or alarms. However, the methods employed for data transfer vary considerably in both cost and capability.

What are the available Always-on connectivity options?

We briefly look at several methods available for transferring data here – WiFi, Cellular, MQTT, and LPWAN.

Wi-Fi is low to zero cost. It is fast and can process large amounts of data but comes with limited availability and is extremely difficult to administer over large fleets of widely distributed assets.

Cellular options offer both excellent coverage and significant volumes of data transfer. Regular cellular networks are designed primarily for human-to-human communications, encompassing voice, video and data. The priority for cellular networks is a seamless and continuous user experience, particularly while a user is on the move. However, the costs of connecting multiple IoT devices via cellular is typically quite high. IoT devices do not always require the high levels of connectivity, or volume of data transfer, offered by cellular networks. Most IoT devices are not mobile and only require infrequent, low levels of data transfer.  Cellular is thus best reserved for when cheaper options are not available OR for solutions that require large amounts of data transfer such as image-based IoT solutions.

MQTT (Message Queue Telemetry Transport) is optimised for sending simple data flows. It suits small, cheap, low-memory and low-power devices. It is less expensive than cellular but still not as cheap as many LPWAN options. Coverage is near-ubiquitous.

Low Power Wide Area Network (LPWAN) offers an excellent solution for always-on IoT devices, filling the gap between short-range wireless networks and mobile (2G/3G/4G) networks. The Low Power (LP), long battery life, aspect of LPWAN is highly attractive for mass-deployed IoT devices, with some solutions requiring only one or two small batteries for up to 5 years of power. With its Wide Area Network (WAN) coverage, LPWAN offers broad range coverage, with low connectivity costs, low running costs and long battery life, making it an optimal solution for mass-deployed IoT devices.

How to choose?

There are several key, obvious criteria:

  • How regular is your data need, considering how you will leverage the data?
  • How widespread is the coverage of your chosen option?
  • Cost – remember it’s not just the cost of data transfer, but different options come with different hardware costs due to the radio needed for the device
  • Can the connectivity be provided for both new-build assets and those already in the field
  • How can the solution provider support you when coverage is NOT available in a certain area

We hope this has provided some brief insight into the, sometimes bewildering, array of connectivity options available to you in 2020.  Nexo is already providing a broad range of connectivity options for your own market and we are happy to discuss your needs with you.  To do, please contact us at

Simple, cooler thinking