Now Cisco is touting wearables as the next form of networking technology – which means that any day soon we will have go back to the wayback engine and dust off all the old gags.

According to Cisco's Visual Networking Index report, there will be more than half a billion wearable devices in use every day by the time 2019 hits.

This figure is assuming that Apple's watch vapourware is launched, works and gets enough traction. The number counts wearable cameras, and fitness trackers. Still, 578 million of them strapped onto people's bodies in just four years' time seems a bit on the high side.

Cisco also estimates that the amount of data from wearables will increase by a factor of 18 during that time, though most of it will filter through users' smartphones. In other words, you're going to be seeing a lot more people tapping at their wrists, something we can't see at all.

Having played with a smart watch, we found them too small to use and it was easier just to pull a phone out of your pocket.

Cisco expects to see smartphone ownership continue to rise to 5.2 billion by 2019. That's almost exactly 1 billion more smartphone users. Naturally, as more people use the Internet on smartphones and wearables, data usage is also expected to rise dramatically.

People used around just 30 exabytes of data in 2014, but that's set to increase exponentially to 292 exabytes before 2020 arrives.