Page 108 - Viva ICSE Computer Studies 8 : E-book

Networking Devices

Let’s learn about some networking devices.

Modem Learn More
Modem is used to enable communication between
The speed of modem is measured in
various computers on a network (mainly Internet). kps (kilobits per second) and varies in
It is connected to the computer port via a telephone range from 14.4 kbps to 56.6 kbps.
line which carries the analog signals. Modem
translates the digital signals used by a computer into analog signals of the kind that travels
by conventional telephone lines. The process of translating digital signals into analog signals
is called modulation. A modem also converts the analog signals into digital signals at the
receiving end of a computing device. This process is called demodulation.

There are mainly two types of modems: internal and external. An internal modem is a card
that is installed into a slot within the CPU case of a computer. On the other hand, an external
modem is a box-shaped device that is connected to the serial port of a computer. For a LAN,
external modem is preferred as it provides faster speed.

Modem Modem

Telephone link

Hub

Hub is a device that is used to connect multiple devices and
computers to a network by fi bre-optic cables. Hub sends all the
data to other parts in the network.

Switch

Switch is a high speed device and consists of many parts.
Switch is aware of the address assigned to each part.
It receives the morning data packets and redirects them
to their destination. Switch is very similar to a hub, but is
smarter than it.

Repeater

Repeater is used to regenerate or replicate a signal. Signals get weak
when transmitted over a long distance. The repeater regenerates
the signal so that it can travel a longer distance with more strength.

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