The total amount of data transmitted over the Internet will triple within the next four years according to forecasts by Cisco. If accurate, the word zettabyte may come into more common usage.

Cisco has made several such forecasts over the past few years. In the one occasion where enough time has passed to check how things played out, the forecast was slightly lower than the reality, but still pretty close.

The forecasts aren’t simply a case of looking at past data use growth and extrapolating it. Cisco says it has looked at two particular factors which will combine to cause rapid future growth. The first is the sheer number of people with Internet access, which Cisco expects to hit 45% of the global population by 2016.

The second is increasing per-person use thanks in particular to online video becoming more prominent. Cisco expects streaming video services to make up 86 percent of all traffic by 2016.

It’s also predicting the average person will “use” 15 Gigabytes (120 Gigabits) per year. If you take out the 55 percent of people who aren’t expected to be online, that works out at 33.3 Gigabytes (266 Gigabits) per year. Of course, I’m guessing there are plenty of Geeks Are Sexy readers who are already over that amount today.

If the three-fold rise in data proves correct, the total annual transmission will go from an estimated 368.8 exabytes last year to 1.3 zettabytes in 2016. An exabyte is a billion gigabytes while a zettabyte is a trillion gigabytes. As a piece of trivia, if we were ever to reach a thousand zettabytes, the term is yottabyte.

Cisco also notes that the 2016 forecast is the equivalent data amount of transferring 328 billion DVDs per year. Look for the MPAA to take liberties with that statistic any day now.

(Image, courtesy of Cisco, shows predicted monthly use by region)