Data Communication, Components of Data Communication, Telecommunication, Devices used in Telecommunication, Distributed Processing, Network Topologies, Network Applications.

1. Chapter -04
Linking Information Technology
Presented By
Ehtesham Akhtar

2. Data Communication
• Data Communication is the exchange
of data (textual, numeric, audio or video data)
between two devices via some form of
transmission medium .

3. Five components of Data
Communication
• Data: The message itself
• Procedures: A mutually agreed upon method
of communication
• Hardware: Equipment doing the sending,
receiving & storing
• Software: Instructions & network operations
• People: Users & computer professionals

4. Telecommunication
• The most common means of communication
over long distances involves the telephone.
• For the successful mergence of computers &
telephones, data must be coded in a form,
compatible with both technologies.
• Computers transmits data as digital signals,
while telephone uses analog signals.

6. Devices used in
Telecommuniction
• Facsimile Machines:
Fax Machines (Stand alone fax machine).
• Modems:
Modems permit 2 computers, linked by analog
telephone equipment, to exchange data.
• Communication Software:
Communication software is the user`s interface with
the modem. These programs aid the user in dialling
up the receiving computer.

7. Distributed Processing
The system software that co ordinates the flow of data around the
network is called network operating system. A variety of
configurations support distributed processing.
•Local Area Networks:
Personal computers working within a network are known as LAN.
•Wide Area Networks:
This type of network spans large geographical areas, & local
telephone company is a part of WAN.
•Value-Added Networks:
VAN is a private network provider, that is hired by a company to
facilitate electronic data interchange (EDI), or provide
other network services.

8. Network Topologies
• Bus Topology:
A Bus Topology connects several computers or
nodes with a single network cable. The Bus
Topology promotes, efficient person to person
communication and sharing of data.

9. Network Topologies
• Ring Topology:
Each node or computer is connected to
each other, ultimately forming a large
circle. Data will travel
from one node to the
next, around the
ring, until it reaches
its appropriate
destination.

10. Network Topologies
• Star Topology:
Star topology is a network topology
where each individual
piece of a network is
attached to a central
node (often called a
hub or switch).

11. Network Topologies
• Hybrid Topology:
Two or more topologies can be linked to
form a hybrid topology.

12. Network Applications
• Electronic Funds Transfer :
Electronic funds transfer (EFT) is
the electronic transfer of money from one
bank account to another, without the direct
intervention of bank staff.

13. Network Applications
• Electronic Data Interchange :
EDI (Electronic Data Interchange) is the
transfer of data from one computer system to
another by standardized message formatting,
without the need for human intervention.