About this interactive
The lesson's two kinds of fiber:
- **Multimode:** a core about 50 microns across. The light bounces back and forth down it, so it attenuates more and is kept to shorter runs. Many places find it works just fine.
- **Single-mode:** a core about 9 microns across, against a 70-micron human hair. The light takes a much straighter path, so it attenuates less, goes much farther and arrives clearer.
Fiber in general beats copper on distance and is immune to EMI; it costs more and is fragile. (In the video, the sentence about light bouncing says "single mode" where it means multimode.)
What you'll learn
- Tell multimode fiber (a wider core of about 50 microns, light bouncing on many paths, more attenuation, shorter runs) from single-mode (about 9 microns, a nearly straight path, less attenuation, long distances)
Aligned to
CompTIA Network+
1.5
Compare and contrast transmission media and transceivers.
Cisco CCNA
1.3
Compare physical interface and cabling types
Cisco CCST Networking
3.2
Differentiate between Wi-Fi, cellular, and wired network technologies
Key terms
- Multimode Fiber
- A fiber optic cable with a larger core diameter (typically 50 microns) that allows light to travel multiple paths, resulting in higher attenuation and shorter effective distances.
- Single-Mode Fiber
- A fiber optic cable with a narrow core diameter (typically 9 microns) that allows light to travel a single straight path, reducing attenuation and enabling longer transmission distances.
- Fiber Optic Cable
- A high-speed physical transmission medium that uses light signals to carry data over long distances, including undersea routes that interconnect global networks.
- Attenuation
- The gradual degradation of a signal's strength and clarity as it travels over a physical medium across distance.
Topics
Multimode Fiber
Single Mode Fiber
Fiber Optic Cable
Interactive
Streak Sort
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