1. NETWORK DEVICES
By:
12BS(CS)02
Computer Science Department , QUEST
Data Communication

2. OUTLINES
o Network Devices.
o Types Of Network Devices.

3. Network Device
Network Devices:
o Any device capable of connecting to a network is considered a
network device. Some networking device are:
o Repeater
o Hubs
o Switch
o Bridge
o Router
o Gateway
o Modem

4. Repeater
o Network repeaters regenerate incoming
electrical, wireless or optical signals. With
physical media like Ethernet or WIFI, data
transmissions can only span a limited
distance before the quality of the signal
degrades. Repeaters attempt to preserve
signal integrity and extend the distance over
which data can safely travel.
o A repeater is an object that increases a
signal's strength, so it can be transmitted
and received over a greater distance without
a loss in quality.
o A radio repeater
retransmits a radio
signal.

5. Hub
o A central device that provide a common connection among the
nodes.
o Hubs are work at the OSI Physical Layer.
o Two types of hubs.
1) Active Hub:- Provide a path for digital signal as well as
regenerate the signal.
2) Passive Hub:-Provide a path for electrical signal.

6. Functioning of a Hub
o Receives a data packet.
o Forwards it to all the remaining ports.

7. Switch
o A network switch (sometimes known as a switching hub) is
a Computer network devices that is used to connect devices
together on a Computer network by performing a form
of Packet switching. A switch is considered more advanced than
a hub because a switch will only send a message to the device
that needs or requests it.

8. What does it do?
o It establishes a temporary connection b/w
the source and the destination and then
terminates the connection when
conversation is done

9. Modulator Demodulator
(MODEM)
o The word "modem" comes from
"modulator- demodulator”
o Modulation: digital information
to analog signal.
o Demodulation: analog signals
back into useful digital
information

10. Bridge
o Bridge are used to divide the network into segment.
o It work in physical and data link layer.
o As physical layer it regenerate the signal.
o As data link layer it check the physical address or MAC address.
o It can filter the traffic on the basis of MAC address.
o It is used to interconnect the two LANs.
o Three types of bridges
1) Transparent bridge.
2) Source routing bridge.
3) Translation bridge.

11. Types of Bridge
1) Transparent bridge
o Perform the function of blocking or forwarding on e basic of
MAC address.
o Ethernet network are the example.
2) Source route bridge
o Use in Token ring network.
o To make the specific decision about how the data is forward
to the network.
3) Translation bridge
o Used to convert one networking to another networking
o Like Token to Ethernet networking.

12. Router
o Router are the device that are connect two
distinct network.
o Router are use the logical address such as IP
address to make the decision.
o It operate the network layer in OSI model.
o Routers have the ability to make intelligent
decisions as to the best path for delivery of
data on the network.

13. Gateway
o Has the ability to connect dissimilar networks.
o Any device that convert one data format t another.
o It cannot change the data itself.
o The conversion from one data format to another takes
time, and so the flow of data through a gateway is always
slower than the flow of data without one.

14. THANK YOU