When it comes to developing your IoT project the choice of connectivity can affect how the solution performs, its effective range, reliability, device battery use as well as how much data of different types it can transfer and at what speed. Although there are many IoT connectivity options available, cellular IoT connectivity is becoming increasingly popular as a simple, scalable and secure way to get your devices connected.
There are essentially two groups of cellular IoT connectivity. These are high data rate cellular, which uses the familiar generations of 3GPP based mobile networks such as 3G, 4G and 5G, and the newer, lower data rate LPWAN (Low Power Wide Area Network) cellular.
High data rate cellular offers comprehensive coverage with fast rates in the Mbps range. As such, these systems are the perfect choice for cellular IoT use-cases that will be using data hungry applications such as real-time video, or for IoT devices that will move around a lot. For example, this option is ideal for providing Wi-Fi on public transport, offering in-vehicle access points supported by a connection to the cellular mobile network.
By contrast, LPWAN cellular offers lower rate data connectivity for IoT devices but compensates with lower power demands and lower bandwidth requirements. Popular technologies in this area include NB-IoT and Cat-M.
Alternatives to cellular connections for IoT devices
Although this blog focuses on cellular, there are numerous other options for IoT connectivity such as Ethernet, which although easy to implement over a hardwired connection does not offer native security.
Wi-Fi is another easy to adopt connectivity option. Compared to Ethernet, it swaps the reliability of hard wiring for the convenience of installing devices where they are needed, without the need to run cables to them. In addition, data is generally encrypted from the IoT device to the Wi-Fi access point although it is then sent ‘in the clear’ over the internet.
Low power devices could use Bluetooth – these devices are usually battery-powered wearables with minimal power demands. However, range is limited to between three and five meters. Zigbee is an option similar to Bluetooth but with a greater range and correspondingly higher power consumption. It is often used for IoT products such as smart lights and home security systems.
You can find out more about some of the other popular options for connecting IoT devices in our blog on the topic.
What are the benefits of cellular IoT connectivity?
Although all options have their merits, for developers producing an IoT solution deployable anywhere, cellular wins hands down. It offers comprehensive security, has high interoperability and scales easily without significant additional overheads.
Possibly the headline benefit for cellular IoT connectivity is the simplicity of deployment. IoT devices can connect to the chosen network using a standard SIM card. SIM cards come in multiple formfactors depending on the device type and requirements, and provides a robust and secure way to get your devices connected. SIM-based cellular connectivity makes bringing a solution into service straightforward once devices are deployed with no need for time consuming and potentially complicated on site set-up to access hardwired networks. Simply deploy your device, remotely activate your SIM, and you are good to go. And with cellular technologies such as eSIM (eUICC) quickly gaining traction, cellular can provide a future proofed and incredibly flexible way to not only get your devices connected, but keep them connected, cost effectively, throughout their lifecycle.
Cellular connectivity is well suited to the massive nature of many IoT deployments. As new technologies such as 5G start to become more broadly available, cellular provides an excellent solution for genuinely large scale IoT deployments. Cellular is also a great choice for deployments that haven’t yet reached large scale but are growing fast. Because the cellular network infrastructure is already in place in most scenarios, a lack of network capacity or coverage will not hold back scaling you deployments. Chances are you will be able to deploy as many devices as you need, wherever they are required and get straight into operation. Bringing us neatly onto the next benefit.
Put simply, cellular networks are almost everywhere and offer connectivity more or less wherever an IoT device might be deployed. Through its existing large-scale infrastructure, cellular IoT connectivity can provide nearly ubiquitous global coverage, giving options for accessibility and positioning of IoT devices that more localized access technologies like Wi-Fi simply cannot match. Black spots are now a thing of the past – with coverage, particularly for LPWAN, extending to underground areas such as subways, into large buildings and people’s homes.
Although the cost of connecting IoT devices to a cellular network was once high, data costs have reduced significantly over the last few years. As such, many cellular data plans allow for significant flexibility in how you use that data and with many devices only sending tiny amounts of data, combined with the other benefits cellular connectivity offers, means that cellular can actually be a highly cost-effective way of connecting your devices compared with other more traditional options such as Wi-Fi.
Security should be a serious consideration for anyone developing an IoT solution, and this is another area where cellular can provide significant advantages compared with other options. Firstly, cellular networks use operator-issued SIM cards to authenticate devices and associate them with a legitimate subscriber making it easier to trust your data. Second, cellular networks are inherently secure. Combining with the benefits of a properly managed connectivity service, private APN controlled network access, secure VPN networking, and the visibility and control offered by a connectivity management platform delivers a high degree of confidence that your data is safe end-to-end.
Impact of different cellular standards on IoT connectivity
Hopefully, by now you’ll appreciate some of the reasons why cellular is becoming such a popular choice for getting devices connected across a large variety of use cases. However, as already mentioned, even within the bucket of cellular technologies, one size does not fit all.
The different characteristics of connectivity types and network generations brings a huge amount of flexibility and can also make the decision a little more complex. From 4G to LTE-M, each has its own attributes that ensure a wide range of IoT solutions with varying degrees of sophistication. For example, the first incarnation of digital cellular networking, 2G, has historically been used for undemanding applications to send basic alerts and information, while consuming very low power. However, most network operators have phased out 2G, so it is no longer a sensible choice and replaced with other options. On the other hand, 3G offers faster data transmission, enabling devices to connect directly to the internet, however, it is also being gradually sunsetted by many network operators, superseded by 4G, which offers even greater bandwidth. Now we then have the arrival of 5G, which many believe will unlock massive IoT on a scale never before possible. It offers support for very data-intensive applications such as self-driving cars, while also supporting a high density of devices and having options for devices that feature lower power consumption.
And we haven’t even begun to talk about LPWAN cellular technologies in any detail.
So while cellular is a great choice, it does have complexity, and it’s essential to think carefully about your device’s specific requirements and match them to the appropriate cellular standard, which ensures optimum performance.
Luckily, Pelion can help. We can provide global IoT connectivity coverage across all major standards, and our team is happy to give advice and guidance to get your project started on the right foot. Feel free to get in touch if you want to chat.