1. Computer Communication and Networking
Abdul Wahab Yaqoob
B.E(Telecom)MUET,CCNA,CCNP,MCSA,CCDA
Department of Information Technology
Campus Dadu ,University of Sindh
Unit #01 Lecture#01
Introduction of Computer Communication and Networking

2. Computer Communication and Networking
Title of Subject : Computer Communication and Networking
Effective : 2K13 Batch
Marks : 100(theory) (Practical)
Credit Hours : 2+1
This Class will meet at: 9:00-11:00 AM on Thursday
Recommended Books 
” Data Communications & Networking”, by Behroz Forouzan
 ” Data and Computer Communications”, by William Stallings
 ” Computer Networks, 4th Edition”, by Andrew S Tanenbaum
Department of Information Technology Sindh U, Campus Dadu 2

3. Computer Communication and Networking
Collection of electronic devices like PDA’s,
Computers,Laptops, Mobiles etc.
Department of Information Technology Sindh U, Campus Dadu 3

4. Computer Communication and Networking
Computer Network aka Network
A Simple Design of Computer Network
Not able to share resources each other
Networking
A Computer Network that shares resources
Between each other
Resources like file sharing/print share etc
Department of Information Technology Sindh U, Campus Dadu 4

5. Computer Communication and Networking
Voice
Video
Data
Data Communication
Raw facts and figure
Only Data
Department of Information Technology Sindh U, Campus Dadu 5

6. Computer Communication and Networking
Basic Elements of Communication System
Every Communication system consists of
Transmitter (Tx)
Medium
Receiver (Rx)
Department of Information Technology Sindh U, Campus Dadu 6

7. Computer Communication and Networking
Basic Elements of Communication System
Department of Information Technology Sindh U, Campus Dadu 7

8. Computer Communication and Networking
Basic Elements of Communication System
Transmitter
“transmit” = send information to the receiver
Uses the most suitable method to convey information
Method depends upon the communication medium
– Audio
– Visual/Video
– Hand gestures, smoke signals…
Communication medium
Literally, medium of communication
Wired and wireless
Receiver
“receiver” = receive/recover information from the transmitter
Receiver designed according to the transmitter
Department of Information Technology Sindh U, Campus Dadu 8

9. Computer Communication and Networking
Communication Medium or Channel
these are the channels over which a message travel
Encoding is different for each type, i.e. electrical impulses,
light pulses, wave patterns
Department of Information Technology Sindh U, Campus Dadu 9

10. Computer Communication and Networking
Transmission Modes - Modes of Communications
One way
Simplex
One person talks, the other listens
•FM radio
•Satellite TV
Two way
Half Duplex
Two people can talk but one at a time
•Walkie-talkie
Both way
Full duplex
Two people can talk simultaneously
•GSM phone call
•PTCL phone call
Department of Information Technology Sindh U, Campus Dadu 10

11. Computer Communication and Networking
Network Components
Hardware (includes devices and media)
Software (services and processes)
Department of Information Technology Sindh U, Campus Dadu 11

12. Computer Communication and Networking
End Devices
End devices form interface with human network & communications network
Originate data flow!
Examples: computers, printers, VoIP Phones, cameras, cell phones, etc.
Commonly referred to as hosts (source or destination of a message)
Each host has an address that will identify it on the network(IP Address).
Role of end devices:
Client (software installed so they can request & display info from the server)
Server (provide information and services to other hosts)
Both client and server
Department of Information Technology Sindh U, Campus Dadu 12

13. Computer Communication and Networking
Intermediary Devices
Role of an intermediary device
Examples: Hubs, switches, access points, routers, modems, etc.
Provides connectivity and manages data flows across network
Works behind the scenes
Determines the path data will travel to get from source to destination
Knows all the paths that exist
Informs other like devices about errors or communication failures
Retimes & retransmits signals as necessary
Department of Information Technology Sindh U, Campus Dadu 13

14. Computer Communication and Networking
Network Types
Local Area Networks (LANs)
A network serving a home, building or campus is considered a Local Area Network (LAN)
Single geographic area, usually a common organization
Administered by a single organization
Provides network services to a common organization
Department of Information Technology Sindh U, Campus Dadu 14

15. Computer Communication and Networking
Network Types
Metropolitan Area Network ( MAN )
A Metropolitan Area Network is a large network that spans a metropolitan area or campus.
Its geographic scope falls between a WAN and LAN.
Department of Information Technology Sindh U, Campus Dadu 15

16. Computer Communication and Networking
Network Types
Wide Area Networks (WANs)
LANs separated by geographic distance are connected by a network known as a Wide Area Network (WAN)
Be able to identify a LAN and a WAN given a similar diagram
X.25
Frame Relay (FR)
Asynchronous Transfer Mode (ATM)
Department of Information Technology Sindh U, Campus Dadu 16

17. Computer Communication and Networking
Network Types
Define the Internet
The internet is defined as a global mesh of interconnected networks
Department of Information Technology Sindh U, Campus Dadu 17

18. Computer Communication and Networking
Network Symbols – be able to recognize
Department of Information Technology Sindh U, Campus Dadu 18