Cisco: Internet traffic will pass a zettabyte this year driven by mobile, will double again in 2019; 5.5B people will own a mobile device by 2020
Phones Will Drive Internet Traffic Past the Zettabyte Mark This Year — It's no real secret that the rise in the world's Internet traffic …
Context & Ripple Effects
Cisco's Visual Networking Index has become the industry's annual yardstick for traffic growth: last year's edition projected mobile data growing tenfold to 25 exabytes a month by 2019 (Cisco's 2015 mobile network report). This year's update crosses a symbolic threshold — total internet traffic passing one zettabyte — and attributes the acceleration squarely to phones.
The forecast lands mid-arc in mobile's takeover of computing: Benedict Evans' year-end tally counted roughly 2.5 billion smartphones already reshaping retail and cars (Mobile is eating the world, 2016 edition). Cisco's numbers are the network-side confirmation of that same shift.
First-order effects
- Carriers face immediate capacity pressure: with traffic doubling again by 2019 and per-user consumption climbing (US data use was on track to pass 6GB/month in 2017), operators must keep adding spectrum and backhaul just to hold service quality flat.
Second-order effects
- Operator economics pivot from signing up new subscribers to monetizing consumption per connection — a shift visible later in US net-adds, where IoT and cars supplied 62% of additions while smartphone penetration sat at 92%.
Third-order effects
- Growth structurally migrates from reach to depth: GSMA data shows 4.6 billion people — 57% of the world — now on mobile internet with subscriber growth slowing from 200M to 160M a year, so future traffic gains come from heavier use per device, which is why Cisco's later index fixated on 5G carrying up to 9% of North American connections by 2022 (Cisco's 5G connection forecast).
- The compounding curve Cisco charted held up: Americans alone consumed over 100M TB of wireless data in 2023, up 36% in a single year — the largest jump on record — validating the zettabyte-era trajectory and keeping infrastructure capex a permanent line item for carriers.
The trend: Global connectivity is shifting from a race to add mobile users to a race to carry exponentially more data per user, making network capacity — not subscriber counts — the industry's defining constraint.