When we think of computer networks, we think of routers and servers and fiber optic cables and laptops and smartphones — we think of the internet. In actuality, though, the visible internet is just the tip of the iceberg. There are secret military networks, and ad hoc wireless networks, and utility companies have sprawling, cellular networks the track everything from the health of oil pipelines and uranium enrichment machines through to the remaining capacity of septic tanks.

Emergency services have their own closed networks, public transport ticketing machines are all networked together, and of course traffic signals and cameras are all networked up. Meteorological agencies have huge networks of weather beacons. Most large buildings (and cities) have sprawling networks of CCTV cameras. And, in the case of large retailers, even individual stock items are networked using NFC (RFID).

At the moment, almost all of these networks are completely disconnected — but what if we connected them all to the internet? What if we extended the internet so that it wasn’t only populated by humans? What if we made an internet of things?

Imagine if everything in the world was connected up to the same network? Every computer, every loaf of bread, every car, every traffic signal, every human. Imagine the possibilities of combining and correlating that data. Before you set off in the morning, you could see the exact, real-time traffic on your smartphone — and you would know what the weather (and air quality) is like at your office/campus. From home, you would know the exact stock levels of your nearest supermarket and the price of gas.

In short, our efficiency would improve dramatically. Instead of having to drive somewhere or phone someone up, every piece of data has already been collected, transmitted at the speed of light, and stored in a massive database that can be accessed from anywhere.

The internet of things wouldn’t only be used by humans, either — things could communicate with each other. For example, your car could communicate with other cars and traffic signals, so that the light always turns green just as you arrive — or, really, with fully autonomous and networked cars, you wouldn’t need signals at all; cars would just automagically avoid each other by braking and accelerating at the right time. Fridges could communicate with supermarkets and arrange food deliveries; ditto natural gas and oil and septic tanks. With an internet of things, we could tack the word “smart” onto almost everything; smart cars, smart homes, smart supermarkets, and even smart cities.

Of course, creating the network that would underpin these smart devices and cities would be a monumental undertaking, but — perhaps unsurprisingly — companies like IBM and Cisco are already working on such systems.

Next page: Rio de Janeiro – the first smart city?