Even though they differ greatly, what analyst and vendor projections all agree on is that the number of connected internet of things devices will essentially go through the roof over the next couple of years. Estimates range anywhere from 20 to 50 billion connected IoT devices by 2020 — with Gartner, for example, projecting 20 billion devices as more a “conservative” estimate, if there ever is a conservative view in light of these stunning figures. But no matter how many billions of devices it will finally be, one thing is for sure — it’s going to be huge!

Source: The darkside of the internet of things: The security challenge | IoT Agenda