Different guided media are as follows
- Twisted pair
Twisted pair is one of the most commonly used communication media. wire pair is usually made up of copper. The pair of wires is twisted together to reduce noise. Noise is an electrical disturbance that can degrade communication. It is normally used in local telephone communication.
it is used for short distance digital data communication. It is also called wire pair. Its speed is 9600 bits per second in a distance of 100 mater. Wire pairs are inexpensive . it has fewer bandwidths than coaxial cable or fiber optics.
- Coaxial cable
Coaxial cable consists of a copper wire core covered by insulating material. The insulated copper wire is covered by copper mesh. It protects the cable from electromagnetic waves. It is the same cable that is used for television. Coaxial cable contains 4 to 22 coaxial units called tubes.
Coaxial cable is used for long-distance telephone lines and local area networks. It is more expensive than twisted pair.
- Fiber Optics
A fiber optic cable transmits data as pulses of light through tiny tubes of glass. A typical fiber optic consists of very narrow strand of glass called core. The strands are thin like human hair. The core is the center of the fiver where light travels. There is a concentric layer of glass around the core called cladding. It reflects the light back into the core. The cladding has a protective coating of plastic called jacket.
An important characteristic of fiber optics is retraction. Refraction is the characteristic of a material to either pass of reflect light. Most telephone companies, ISPs and cable TV operators are using fiber optics in their networks.
Advantages of fiber optics
1 Fiber optics network at a very high speed.
2 The information carrying capacity of fiber optics is very high.
3 Fiber optics is lighter and smaller in size.
4 It is more secure and reliable form of data transmission.
5 It is not affected by electromagnetic waves.
Disadvantages of Fiber Optics
1 It is difficult to install.
2 It is expensive.