6 Popular options for connecting IoT devices

March 19, 2021 — 6 min read

Choosing the best option for connecting your IoT devices isn't as hard as it seems. While there are a whole range of possibilities, and often your projects will shift connection type as they move from proof of concept through early trials and into managed production roll-out, the number of final production options suitable for your system narrows pretty quickly as your device evolves and the system management processes become clear. Let’s look at the main options:

Ethernet

Easy to implement and well understood, cheap, easy to commission, and high bandwidth; Ethernet is a great way to connect IoT devices where you need a hard-line uninterrupted link to your device, and critically have the physical infrastructure to simply hook devices up, or you’re taking the first steps brings up a new IoT solution. Data transmitted over ethernet isn't secure, so your data and device management actions are subject to attack from any other equipment on the same network unless you take specific steps to encrypt your messages. If you're deploying equipment into a new construction site then Ethernet can work well, but if your IoT solution is a retrofit system then it's very likely that the in-house ethernet link is out of bounds due to local networking policies.

Wi-Fi

Again easy to implement and well-understood Wi-Fi extends the Ethernet points above and trades hard-line reliability for the flexibility of installing your device in the locations that it's required without routing cables to a network switch. Data is generally encrypted from your device to the Wi-Fi access point but will be sent in the clear over the access point's internet connection unless you add your own IoT system encryption. Points to consider if you are connecting your IoT devices with Wi-Fi are the onboarding of credentials required to connect devices to the Wi-Fi network, and ensuring that your entire system is resilient to connectivity outages caused by bandwidth capacity in busy Wi-Fi areas or interference from other equipment operating in the same area. If your device is working in a consumer or enterprise space then Wi-Fi can be ideal but watch out for the power requirements.

Bluetooth

A common option for low power connected devices, typically battery-powered wearables that have a limited connection duration only when the device is being used. Range is typically low in the 3-5m area, and a secondary device is required to bridge the data to an internet connection. Often Bluetooth is bridged through mobile phones, but dedicated gateways are also popular in fixed applications like domestic health monitoring.

Zigbee

Another wireless solution frequently used in domestic products and, like Bluetooth, requires a bridge to pass device data to the internet. Range is longer for Zigbee than for Bluetooth and power consumption is higher making this a frequent option for smart home products like light bulbs and ceiling fans.

Cellular

Cellular connectivity through mobile phone networks offers a very different approach to IoT connectivity because it makes use of existing large-scale infrastructure and puts a much greater level of control and management directly into the IoT system operator's hands instead of relying on on-site connectivity management. This makes cellular an ideal fit for connecting IoT devices when you know that your devices are going to operate in areas across the country with ubiquitous cellular coverage.

High data rate cellular - Connectivity options like 3G, 4G, and 5G cellular connections provide wide coverage multi MBps data connections that are ideal for real-time video streaming or other data-intensive applications, or highly mobile devices. This option is a great fit both for applications like public transport Wi-Fi provision using in-vehicle access points with a cellular backhaul link; or for mobile devices where high connection availability is required on a very broad basis like those implementing vehicle or package GPS tracking systems.

LPWAN cellular - Extending the traditional high data rate cellular services are newer low data rate methods with corresponding low power requirements. NB-IoT and Cat-M are increasingly popular LPWAN technologies and can be ideal as a balance for the large scale connection requirements of a widely distributed IoT system combined with the low bandwidth requirements traditionally associated with IoT devices, and low power requirements. These connectivity options are in a state of mass deployment at this time compared to the regular cellular options that connect our mobile phones but are rolling out internationally at an increased rate. Management of IoT focused cellular connections lines up well with traditional cellular options which opens the door to systems migrating future devices over as hardware is updated.

LPWAN Managed Networks

Local self-managed IoT wireless networks can be a great solution when you need to deploy wireless devices with your own access points and gateways in areas that don’t have an existing infrastructure or where you want a self-managed, fully isolated infrastructure. Compared to Wi-Fi network connections that place large power requirements on connected devices, the IoT focused LPWAN network options that you can deploy are designed to operate at lower bandwidths, draw less power, and operate in a fault-tolerant way with re-routed mesh network topologies in place. LoRaWAN and more recently Wi-SUN solutions offer long-range connections between gateways and devices with the gateway performing both a dynamic MESH function and a bridge to the internet. Wi-SUN has high adoption in smart cities and by utilities service providers who like the easy of automatic data path re-routing and the operational range to connect utility meters to gateways.

Pelion services address all these connection methods and give you a set of tools to secure and manage your devices.

The Pelion IoT Connectivity service is tightly built around cellular options with features to both administer and manage cellular connections at scale throughout a device's lifecycle from the production line to deployment, view ongoing connection analytics, and decommissioning devices at the end as they’re taken out of use. The APN architecture of our connectivity service means that make highly valuable insights available to you about how your cellular connections are performing. Our alert and automation rules handle the day-to-day activation of connections or the flagging of devices with early indications of trustable data concerns. Our VPN options to our APN servers can be used to give you even more data security and highly trustable device data.