What Is IoT?

Sensors monitor and collect data on events in the surrounding environment, while actuators receive the data and create an action from it. For example, a sensor might detect increased moisture in the atmosphere of an office building, and then the actuator responds by activating a dehumidifier.

Sensors can detect all manner of things, from humidity level to light levels, noise, motion, and just about any kind of environmental change. Actuators, meanwhile, can trigger a variety of responses, such as activating motors or alarms.

Connectivity is a crucial part of IoT. Our connected physical devices would be useless if they couldn’t communicate data between them, and a variety of options are available. For instance, there’s WiFi, which has a limited range but can transfer data at a high capacity, so it is often used in domestic IoT.

Similarly, Bluetooth works very well in smaller-scale IoT, as it prioritises low-energy consumption and seamless connectivity. It is commonly used to link smartphones, televisions, and other smart devices at home. Low Power Wide Area Network (LPWAN) solutions are almost the exact opposite – transmitting small amounts of data over larger areas, so are useful for operating things like trail cameras and asset tracking.

Then there are cellular connections, with 4G and 5G being the best known. These transfer data at high speeds and offer wide coverage, so they are commonly used for industrial IoT networks. Traffic cameras, robotic assembly lines in factories, and fleet management logistics frequently rely on 4G or 5G connectivity.

Edge computing processes data close to where it is generated – on the device itself or on a nearby gateway or server. This can reduce delays, lower the amount of IoT data sent across a network and allow some systems to continue working when cloud connectivity is limited.

Cloud computing processes and stores data in remote data centres. It can support centralised device management, large-scale storage and analysis across many devices and locations.

Many IoT systems use both. Edge computing can handle immediate decisions, such as stopping a machine when a dangerous reading is detected, while the cloud supports longer-term analysis, reporting and coordination across the wider network.

Middleware is the software that sits between the various devices that make up an IoT network and enables them to communicate with one another. It simplifies the complexities of how devices speak with one another, and handles firmware updates, health monitoring, and various other functions.

Examples of middleware include:

• FIWARE – an open-source platform commonly used for smart cities and other data-sharing projects.
• Eclipse Kura – an open-source middleware used for IoT gateways.
• Microsoft Azure IoT Hub - a cloud-based middleware that manages and connects devices.

You may also have encountered Google Cloud IoT Core, which was officially retired in 2023, but was a popular middleware choice.

Middleware is sometimes referred to as an IoT platform, although strictly speaking, they’re a separate thing. Where middleware is a specific layer, the platform is a broader, more encompassing software solution, and middleware forms a part of it. Platforms include analytics tools and data visualisation, and a user interface.

As IoT systems handle large volumes of data, there are several privacy concerns to take into account. IoT engineers have to think about issues such as unsecured networks, weak passwords, outdated software and other factors that make them vulnerable to data theft. Plus, there’s the fact that most IoT devices are small, so they can easily be stolen and tampered with.

IoT professionals have various resources to tackle security risks. The three main areas to consider are device, network, and operational security. There is no single technology that can protect all three, but careful integration of denial-of-service resistance, event logging, data encryption, and asset-tracking can all improve resilience.