Page 187 - Computer_Science_F5

Computer Science Transmission media Sender Receiver
The transmission medium is the pathway that can send data and information from the
source to the destination. For example, the transmission medium for the conversation
between you as a student and
teacher in class is air. Also,
FOR ONLINE READING ONLY
when you have a written
message such as a letter, the
transmission medium can be a
mail carrier, truck, or aeroplane.
Figure 3.30 illustrates the Transimission Media
transmission of data from the Figure 3.30: Transmission of data from sender to
sender to the destination. receiver through a medium

In data communication, transmission media are the links that carry messages between
two or more communicating devices. Computers and other telecommunication
devices use signals to represent data and information. These signals are transmitted
in the form of electromagnetic energy from one device to another. The transmission
medium in data communication can therefore be more specific and is usually free
space, metallic cable, or fibre optic cable. Transmission media can be categorised as
guided or unguided media. Figure 3.31 shows the classification of transmission media.

Transimission Media

Bounded/Guided media Unbounded/unguided media

Twisted cable Coaxial cable Fibre optic Radio Microwave
cable transmission transmission

Shielded Unshielded
Broadband
Baseball

Figure 3.31: Classification of the transmission medium

Guided transmission media
In guided transmission media, there is a physical link made of wire/cable through
which data in terms of signals are propagated between the source and destination.

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for Advanced Secondary Schools

Computer Science Form 5.indd 178 23/07/2024 12:33