Fiber Optic Cabling Explained

Sending Light Instead of Electricity

Fiber optic cable carries data as pulses of light through an extremely thin strand of glass or plastic, rather than as electrical signals through copper - a fundamentally different transmission approach with several major advantages.

How Light Is Kept Traveling Inside the Fiber

Light pulse -> bounces along the inside of the fiber's core via total internal reflection ->
             continues traveling forward, contained within the strand

The physical properties of the glass core and its surrounding cladding cause light entering at the right angle to reflect internally rather than escaping outward - effectively guiding it along the fiber's length, even around gentle bends.

Key Advantages Over Copper Cabling

Single-Mode vs Multi-Mode Fiber

Single-mode fiber uses an extremely narrow core, sending light in essentially one straight path - suited to very long distances, like connections between cities. Multi-mode fiber has a wider core allowing light to travel multiple paths at once, cheaper to produce but suited to shorter distances, like within a single building.

Why Fiber Hasn't Completely Replaced Copper Everywhere

Fiber cabling and the equipment needed to convert between light and electrical signals are notably more expensive than copper equivalents, and fiber is more fragile and harder to work with physically. This is why copper remains common for short, low-cost connections (like a single device to a wall jack), while fiber dominates long-distance and high-capacity backbone connections.