2. Ch#04
Linking Information Technology
Presented to:
Zeeshan Abbas.
Presented By:
Sardar Mubashir Zakir. (1421-315232)
Khubaib Ayub. (1421-315312)
Akash Ashraf. (1421-315233)
Raja Tayyab Hussain. (1421-315243)
Maaz Ali. (1421-315246)

3. Introduction To Data
Communication
• Data communication deals with the transmission of signals in reliable and
efficient manner , using some media .
• Data communication is the process of transferring data from one point to
another .

4. Basic Components Of Data Communication
• Data communication consist on the following components .
Transmitter : It is used to transmit the data . Examples are :
I. Terminal
II. Computer
Medium : The communication streams through which the data is being
transmitted . Examples are :
I. Fiber optics
II. Telephone lines
III. Radio Frequencies
IV. Infrared Wireless

5. Receiver : It receives the data that was transmitted . Examples are :
I. Printer
II. Terminal

6. Telecommunication
• Telecommunication or telecom is the transmission of signals over long distances .
• A telecommunication system requires an analog or digital transmitter , a compatible
receiver and a physical (cable or wire) or non-physical (wireless) connection .
Examples of Telecommunication :-
Examples of telecommunication system are :
I. Telephone network
II. Radio Broadcasting
III. Computer network and Internet
Teleprocessing
• Teleprocessing is the capability of a computer to connecting with another computer or
network device .
• Such as the connection between a computer and a central computer (server).

7. Telecommuting
• Telecommuting is a latest trend in business through which an employee can work from
home , making use of internet without going to the office .
• The technologies used in telecommuting are :
RAS(remote access service) : RAS is the ability to access a computer from a
remote location.
GPRS : use to connect with laptop and mobiles .
VPS (Virtual Private Server ) Also called Virtual Dedicated Server .
It is a virtual machine sold as a service by an internet hosting
service .

8. Modem
• Modem stands for modulator – demodulator .
• A modem is an electronic device , converts the digital signal to analog signal and
converts analog signal to digital signal.
• Modulation ( conversion of digital signal to analog signal ).
• Demodulation ( conversion of analog signal to digital signal ).

9. Types of modem
There are the following types of modem .
I. External Modem
II. Internal Modem
III. Optical Modem
IV. Digital Modem

10. Sardar Mubashir Zakir
1421-315232

11. What is topolgy ?
 The way in which connections are made is called the topology
of the network.
 Network topology specifically refers to the physically layout of
the network.
 Especially the locations of the computers and how the cable is
run between them.

12. Types of topologies
 These are the some types of topologies.
 Bus topology
 Star topology
 Ring topology
 Hybrid topology

13. BUS TOPOLOGY
 The bus topology is often used when a network installation is small, simple or
temporary.
 If one computer fails the network will continue working.
 If one hub fails only the computer is connected to it will fail.

14. STAR TOPOLOGY
 Easy to add a new computer in a network.
 In star topology, all the cables run from the computers to a central location, where
a device called hub connects them all.
 If single computer failure do not bring down the whole network.

15. RING TOPOLOGY
 In ring topology, each computer is connected to the next computer, with the last
one connected to the first.
 Each computer act as a receiver.
 The message flow around the ring in one direction.

16. HYBRID TOPOLOGY
 Hybrid topology is the combination of two topologies.

17. AkasH AsHraF
1421-315233

18. LAN ( local area network )
 A local area network (LAN) is a collection of networking equipments located geo
graphically close together.

19. LOCAL AREA NETWORK
 Personal computer LANs
_______ low cost.
_______ limited data rate.
_______ high data rate.
_______ high speed interface.
_______ limited distance.
_______ limited no of devices.

20. LOCAL AREA NETWORK
 A LAN is a computer network that cover small area ( home, office, building,
campus ).
 LAN have higher data rate ( 10Mbps to 40Gbps ) as compared to WANs.
 A LAN utilizes high speed data transfer capabilities.

21. Catagorization of LAN
 On the basis of
________ their size
________ their transmission technology
________ their topology

22. Example of LANs
 3 different examples of LANs :
________ Ring topology
________ Bus topology
________ Star topology

23. Khubaib
1421-315312

24. WAN ( wide area network )
 A wide area network (WAN), on the other hand has no geographical limit.

25. WIDE AREA NETWORK
 It can connect computers and other devices on opposite of the world.
 A wide area network (WAN) is made up of a number of interconnected LAN.
 WAN covered a large number of area.

26. WIDE AREA NETWORK
 ADVANTAGES
_________ Simple.
_________ Wide distance.
_________ Faster then LAN.

27. WIDE AREA NRTWORK
 DISADVANTAGES
_________ Expensive.
_________ Slow speed.
_________ Difficult trouble shooting.

28. Maaz Ali
1421-315246

29. METROPOLITAN AREA NETWORK
 MANs are large computer networks usually spanning a city.

30. METROPOLITAN AREA NETWORK
 Metropolitan are network is a large computer network that usually span a city or
campus.
 A metropolitan are networks are formed with many local area network (LANs).
 It provide a fast communication via high_speed such as, fibre optic cables.

31. ADVANTAGES
 It provide a good backbone for a large network and provides greater access to
WAN.
 It is most common to see MANs on university campuses.

32. DISADVANTAGES
 More cables required for a man connection from one place to another place.
 The large the network becomes difficult to mange.
 it is difficult to make the system secure from hackers and industrial geographical
regions.