Transmission Media

Types of Transmission Media

1. Guided
2. Unguided

Guided Transmission Media

• Twisted Pair Cable
• Coaxial Cable
• Fiber Optic Cable

Fiber Optic Cable

• Newer Transmission Media: Used by telephone companies and private companies for long-distance and local data communication networks.
• Light Sources Required: Uses Injection Laser Diode (ILD) or Light Emitting Diode (LED).

Structure

1. Plastic Jacket
2. Glass or Plastic Cladding
3. Fiber Core

Types of Fiber Optics

1. Multimode Step-Index Fiber
   • Reflective walls of the fiber move light pulses to the receiver.
2. Multimode Graded-Index Fiber
   • Refracts light towards the center of the fiber through variation in density.
3. Single Mode Fiber
   • Guides light down the center of an extremely narrow core.

Advantages of Fiber Optics

• Greater Capacity: Bandwidth up to 2 Gbps.
• Smaller Size and Lighter Weight
• Lower Attenuation Problems
• High Immunity to Environmental Interferences
• High Security: Difficult to tap and lacks signal radiation.

Disadvantages of Fiber Optics

• Expensive Over Short Distances
• Requires Highly Skilled Installers
• Difficult to Add Additional Nodes