You think the internet lives in the cloud. It lies at the bottom of the ocean.
Modern submarine cables transmit data at up to 340 Tbps. Light pulses travel through hair-thin glass fibers at 200,000 km/s, bouncing continuously.
Optical repeaters sit every 80 km on the ocean floor to boost fading light, powered by 10,000V DC sent through the cable's core from shore.
Sharks occasionally bite through cables, attracted to their electromagnetic fields. Today, vulnerable zones use steel and Kevlar-like armor wrapping.
Specialized cable ships hold up to 8,000 km of cable. They move at 6 knots while laying cable with millimeter precision using GPS and sonar arrays.
A ship's dragged anchor or a deliberate submarine attack can silence a country. In 2022, Tonga was completely isolated for five weeks after a volcanic eruption severed its only link.
The cables emerge from the sea into hyper-secure concrete bunkers on beaches worldwide, where 10,000V power is injected and light is routed to terrestrial data centers.
When a break occurs, ROVs (Remotely Operated Vehicles) dive thousands of meters to retrieve the ends, haul them to the surface ship, and splice glass strands thinner than a hair.
Historically funded by telecom consortiums, today over 60% of new transoceanic capacity is being built exclusively by Google, Meta, Amazon, and Microsoft.
Over 95% of global internet capacity is carried by cables owned or co-owned by five companies: Google, Meta, Amazon, Microsoft, and a handful of telecoms. The internet is not neutral infrastructure — it is privately held.
In 2022, cables were severed near Tonga, isolating 100,000 people for five weeks. In wartime, submarines could sever internet between continents. NATO has classified submarine cable attacks as a critical national security threat.
Near shorelines cables are buried, but in deep water they simply rest on the ocean floor. A dragging ship anchor can silence a region's internet in seconds. Over 100 cable faults are repaired every year.
Every glowing line is a real submarine cable route connecting our world's information
Route data sourced from TeleGeography SubmarineCableMap & ITU Global ICT Statistics
The next time you send a message from Dhaka to New York, remember: your data traveled to a cable landing station, was converted to light, shot through a glass fiber thinner than your finger across 15,000 km of crushing darkness and arrived in 60 milliseconds.