When people imagine the internet, they often picture satellites floating in space beaming data across the planet. In reality, that image is only a small part of the story. More than 95% of global internet data travels through something far less visible but far more important: undersea cables lying quietly on the ocean floor.
The Hidden Backbone of the Internet
Undersea cables are long fiber-optic lines laid across oceans, connecting continents and countries. These cables form the backbone of the global internet, carrying emails, video calls, cloud data, financial transactions, and streaming content every second. Each cable contains bundles of fiber strands thinner than a human hair, yet capable of transmitting enormous amounts of data at near-light speed.
Unlike satellites, which have limited bandwidth and higher latency, fiber-optic cables offer faster speeds, lower delays, and higher reliability. This is why most internet traffic depends on cables rather than space-based systems.
Why Satellites Handle Only a Small Share
Satellites play an important role in remote regions and emergency communications, but they handle only a tiny fraction of global data. The reason is simple: satellites are expensive to operate, slower due to long signal travel distances, and limited in how much data they can transmit at once.
Undersea cables, once installed, can operate for decades while continuously upgrading their data capacity through improved technology at cable landing stations.
How Undersea Cables Are Laid
Specialized ships carefully place these cables across the ocean floor, avoiding deep trenches, coral reefs, and geological fault lines. In shallow coastal areas, cables are often buried beneath the seabed for protection from anchors and fishing equipment.
- Most cables are about the thickness of a garden hose
- They can stretch for thousands of kilometers
- Modern cables transmit terabits of data per second
Why They Matter More Than Ever
As cloud computing, video streaming, artificial intelligence, and online services continue to grow, undersea cables have become more critical than ever. A single cable outage can slow down internet speeds across entire regions, highlighting just how dependent modern life is on this hidden infrastructure.
So the next time you make a video call, stream a movie, or send a message across continents, remember this surprising truth: your data is most likely traveling silently along the ocean floor, not through space.