Transmission media enables computers to send and receive messages by carrying signals through cables, light, or radio waves. There are two main types: guided media, which uses physical paths like cables; and wireless media, which transmits through air without a direct path. Factors like bandwidth and interference affect the quality and maximum distance of communication. Different media have their own strengths and limitations for uses like speed, security, cost, and ease of installation.

1. Transmission Media Presentation Transcript
• 1. TRANSMISSION MEDIAByILLUMINATIGROUP 05
• 2. On any network, the various entities must communicate through some form of media.Just
as human scan communicate through telephone wires or sound waves in the air, computers
can communicate through cables, light, and radio waves.Transmission media enables
computers to send and receive messages but do not guarantee that the messages will be
understood.2ILLUMINATI
• 3. Communication is possible only if information is encoded in a signal, and the signal is
carried on a transmission ,the characteristics of the signal and of the medium both determine
the quality of the communication medium.There are two main groups of transmission media,
namely the guided medium and the wireless medium.3ILLUMINATI
• 4. For the guided medium, there is a physical path (such as a cable) for electromagnetic
wave propagation.For the wireless medium, however, the electromagnetic wave is
transmitted through air, water, or vacuum. A wireless medium is also called an unguided
medium.4ILLUMINATI
• 5. CHARACTERISTICSA good transmission medium should provide communication with
good quality at long distance.For voice communication, quality of communication is
determined by the voice quality.For data communication, however, the quality of
communication is mainly determined by the effective data rate of
communication.5ILLUMINATI
• 6. FACTORS AFFECTING DATA COMMUNICATION DISTANCE OF A MEDIUM
Communication bandwidth of the medium Interference The transmission
impairments6ILLUMINATI
• 7. The bandwidth of a medium determines the signal frequencies that can be carried in the
medium.A wide bandwidth, or broadband, usually allows communication at a higher data
rate.7ILLUMINATI
• 8. AttenuationDistortion during signal propagation Noises.REASONS FOR
TRANSMISSION IMPAIRENCE8ILLUMINATI
• 9. TYPES ofTRANSMISSION MEDIA9ILLUMINATI
• 10. 10ILLUMINATI
• 11. Guided MediaGuided media includes everything that ‘guides’ the transmission. That
usually takes the form of some sort of a wire. Usually copper, but can also be optical
fibre.11ILLUMINATI
• 12. Twisted Pair CableA transmission medium consisting of pairs of twisted copper
wires.We can transmit 1 Mbps over short distances (less than 100m).They are mainly used to
transmit analog signals, but they can be used for digital signals.12ILLUMINATI
• 13. Twisted Pair Cable13ILLUMINATI
• 14. Coaxial Cable In its simplest form, coaxial consists of a core made of solid copper
surrounded by insulation, a braided metal shielding, and an outer cover. A transmission
medium consisting of thickly insulated copper wire, which can transmit a large volume of
data than twisted wire.14ILLUMINATI
• 15. Coaxial Cable15ILLUMINATI
• 16. Optical Fiber Optical fiber consists of a glass core, surrounded by a glass cladding with
slightly lower refractive index. In most networks fiber-optic cable is used as the high-speed
backbone, and twisted wire and coaxial cable are used to connect the backbone to individual
devices.16ILLUMINATI
• 17. Optical Fiber17ILLUMINATI
• 18. Unguided MediaUnguided media is still ‘media’ (stuff that signal travels though). The
trick is that the media is usually not directional, like air, space, etc. Because the effect is

2. usually much wider than with guided media, there have been a lot of regulation, licensing,
and standardization of transmissions via unguided media.18ILLUMINATI
• 19. Wireless Transmission Wireless transmission that sends signals through air or space
without any physical wire. Common uses of wireless data transmission include pagers,
cellular telephones, microwave transmissions, communication satellites, mobile data
networks, personal digital assistants, television remote controls.19ILLUMINATI
• 20. SOME BASIC DIFFERENCES
• 21. It is inexpensive and already is in use.Twisted wires are slow, high-speed transmission
causes interference (crosstalk).Limiting factors: skin effect & radiation effect.Twisted
Wire21ILLUMINATI
• 22. It is often used in place of twisted wire for important links in a network because it is a
faster.More interference-free transmission medium (speed: 200 megabits per
second).Coaxial cable is thick, is hard to wire in many buildings. It does not support analog
conversations.Coaxial Cable22ILLUMINATI
• 23. Optical fibers are faster, lighter, and suitable for transferring large amount of data.Fiber-
optic cable is more difficult to work with, more expensive. Its difficult to install
them.Optical Fiber23ILLUMINATI
• 24. Optical fiber cable differs from both these transmission media in that it carries the
transmitted information in the form of a fluctuating beam of light in a glass fiber. Light
transmission has much wider bandwidth, thus enabling the transmission rate of hundreds of
megabits per second. Comparison24ILLUMINATI
• 25. Optical transmission is immune to electromagnetic interference and crosstalk. While
others are immune to interference.Optical fibers have less loss of signal strength than
copper, after every 30 miles we need to use a repeater, whereas in copper, we should insert
repeaters at an interval of 2.8 miles . Optical fiber is more secure, no easy tapping on the
cable, like in copper. But optical fibers are more expensive than other two cables.
25ILLUMINATI
• 26. Bandwidth: The difference between the lowest and highest frequency signals that can be
transmitted across a transmission line or communication system.Interference: The distortion
on the signal in transmission due to unwanted signals from outside sources.KEY
Terms26ILLUMINATI
• 27. Transmission Impairments: Attenuation, distortion, or noises that will degrade the signal
quality during transmission.Attenuation: The loss of a signal’s energy when the signal is
transmitted across a medium.Signal Distortion: Any change in a signal during signal
transmission.27ILLUMINATI
• 28. Noises: Random signals that can be picked up during signal transmission and result in
degradation or distortion of data.Trunk Circuits: The communication circuits between two
switching offices.28ILLUMINATI
• 29. In summary, transmission media are essential for communication systems. Signals that
carry information can be transmitted on a transmission medium for communication
purposes. The transmission characteristics of the medium in use are important because they
directly affect the communication quality. Since different types of transmission media have
different transmission characteristics and costs, they are used in different (and the most
suited) applications.Conclusion29ILLUMINATI
• 30. 30ILLUMINATITHANK YO