What is fiber optic?#
Fiber optic is a strand of glass thinner than a hair that carries data as pulses of light. Because light travels fast in glass and does not weaken much, it can move huge amounts of data over very long distances without loss.
How does it differ from copper cable?#
- Speed and capacity: many times that of DSL.
- Signal loss: very low over long distances.
- Interference: immune to electrical disturbance and lightning.
- Stability: lower latency and a steadier connection.
Fiber in the structure of the internet#
Most of the global internet backbone, including undersea cables, is fiber. Carriers lay fiber between cities and data centers, and some bring it all the way to your doorstep (FTTH). In some areas, fiber comes to the building or the neighborhood cabinet and the rest of the way is copper.
Limitations#
Installation takes cost and time, and it is not available everywhere. Fiber is more fragile than copper, and sharp bends damage it. Also, your final speed does not depend only on the cable type; your carrier's plan and your router matter too.
Where you encounter it#
When choosing home internet, in the advertising of carriers and ISPs, and in data centers and corporate networks.