Explain different transmission media along with diagram & it advantages & disadvantages

Transmission media refers to the material or substance that can propagate energy waves, such as electromagnetic waves. They are the physical pathways that connect computers, other devices, and people on a network. The transmission media is categorized into two types: Guided (Wired) and Unguided (Wireless).

1. Guided Media (Wired): In guided media, the data signals are bounded to a specific path like cables. It includes:

   a. Twisted Pair Cable: It consists of a pair of wires twisted together. The twisting can avoid noise that can interfere with signal quality.

   

   Advantages:

   • Cheap and easy to install.
   • Suitable for small networks.

   Disadvantages:

   • Limited range.
   • Susceptible to noise and signal distortion.

   b. Coaxial Cable: It consists of a single copper wire surrounded by several layers including an insulating material, a metallic shield, and a plastic cover.

   

   Advantages:

   • Greater bandwidth.
   • Can be installed with relatively long distances between amplifiers.

   Disadvantages:

   • Expensive and difficult to install.
   • Susceptible to noise if not properly shielded.

   c. Optical Fiber: It uses light signals to transmit data. It consists of a core surrounded by a cladding layer, both made of high-quality silica glass.

   

   Advantages:

   • Extremely high data transmission rate.
   • Not susceptible to electromagnetic interference.

   Disadvantages:

   • Very expensive.
   • Difficult to install and maintain.

2. Unguided Media (Wireless): In unguided media, the data signals are not bounded to a specific path and are broadcasted through air or water. It includes:

   a. Radio Waves: They have the longest wavelength in the electromagnetic spectrum and can be used for long-distance communication.

   Advantages:

   • Can penetrate through walls.
   • Suitable for long-distance communication.

   Disadvantages:

   • Low frequency, hence low data rate.
   • Susceptible to interference from other electronic devices and weather conditions.

   b. Microwaves: They have a shorter wavelength and are used for long-distance telephone communication, cellular telephony, and TV distribution.

   Advantages:

   • High frequency, hence high data rate.
   • Can be focused in a narrow beam and can travel long distances.

   Disadvantages:

   • Cannot penetrate through buildings.
   • Require line-of-sight communication.

   c. Infrared: They are used for short-range communication such as television remote controls and wireless LANs.

   Advantages:

   • Cannot penetrate through walls and hence more secure.
   • High frequency, hence high data rate.

   Disadvantages:

   • Short range.
   • Require line-of-sight communication.