Course Title: IT IN BUSINESS

Course Instructor:

ADEEL ANJUM

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1BY ADEEL ANJUM (MCS, CCNA,WEB DEVELOPER)

Chapter No Chapter Name Page No

1. INTRODUCTION 01

2. INPUT & OUT PUT DEVICES 251

3. SOFTWARE 117

4. HARDWARE 117

5. COMMUNICATIONS & NETWORKS 309

6. INTERNET 49

2

Course Contents

BY ADEEL ANJUM (MCS, CCNA,WEB DEVELOPER)

DATA COMMUNICATION

• Communication is process of transferring messages from one device to another device. There are three elements of data communication.

• Sender

• Receiver

• medium

diagram

SENDER RECIEVER

LINK

NETWORK

• Connectivity of two or more than two devices so that they can communicate. connectivity is done through hardware and communication is done through software. so network is combination of both hardware and software.

NETWORKS

ADVANTAGES OF NETWORK

• Sharing of peripheral devices:

2. Sharing of data:

3. Better communication:

4. Access to database:

Types Of Network

Network is divided into three main types

• LAN (Local area network)

• MAN (Metropolitan area network)

• WAN (wide area network)

• LAN• LAN range is usually within a mile one

office ,one building or within in campus of university.

• MANMAN is a network within a city. or network between cities.

• WANWAN stand for wide area network. It is communication that covers a wide area such as a country .internet is the example of WAN.

TOPOLOGY

TOPOLOGY

STAR BUS RINGMESH

TOPOLOGIES

• The logical layout ,or shape of network is called topology. The basic topologies are.

1. Star

2. Ring

3. Bus

4. Mesh

1.STAR TOPOLOGY

In star topology network all computers and other devices are connected to a central server in star topology HUB is used.

The advantage of this topology is if connection is broken between any communication device and the HUB, the rest of the devices on the network will work. it is easy to install and reconfigure.

STAR TOPOLOGY

2.BUS TOPOLOGY

In a bus topology all devices are connected to a single wire. There is no central server.The advantage of a bus network is easy to install. it use less cabling as compared to mesh and star topology.Disadvantage is that if a connection is broken the entire network may stop working

BUS TOPOLOGY

INTER NETWORK

TokenRing

Private Nets

3.RING TOPOLOGY

A ring topology is one in which all computers are connected in a continuous loop. The message flow in one direction. If a connection is broken the entire network will stop working.

RINGTOPOLOGY

4.MESH TOPOLOGY

In mesh topology every device has a dedicate link to every other device. dedicated mean that link carries traffic only between the two devices it connect. a fully connected mesh ha n(n-1)/2 physical links. every device ha n-1 input output port.

Advantages and disadvantagesof mesh topology

A mesh topology is robust. if one link become unusable it will not effect all network.

Disadvantage is cabling and number of input and out put ports required.

installation and reconnection is difficult.

MESH TOPOLOGY

DATA TRANSMISSION MODES

• There are three ways or three modes of data transmission. These are as follow

1. SIMPLEX

2. HALF DUPLEX

3. FULL DUPLEX

1.SIMPLEX

In this mode data is transmitted unidirectional. Data can only flow in one direction.

For example you can listen to your favorite radio station but you cannot talk back.

2.HALF DUPLEX

In half duplex ,system can transmit data in both direction at a time. Half duplex line can alternatively send and receive data. It requires two wires. This is most common type of transmission for voice communication because only one person speak at a time. you can either talk or listen but you cannot do both at the same time.

3.FULL DUPLEX

with full duplex ,data can flow in both direction at the same time. a full duplex line is faster ,since it avoid the delay that occurs in a half duplex .for example client send data to central computer at the same time central computer sends data to client. full duplex is also called two way transmission.

NETWORK LINKING DEVICES

1. HUB

2. SWITCH

3. BRIDGE

4. ROUTER

1.HUB

HUB is common connection point. with HUB Bandwidth is shared among all comopnents.HUB is a half duplex device, meaning it transmits data in both direction but only in one direction.it also broadcast data.

Physical

All devices in the same broadcast domainDevices share the same bandwidth

Hubs operate at Physical Layer

AA BB CC DD

2.SWITCH

A switch is a device which connects computers to a network. a switch is a full duplex device. switch is intelligent device. First time switch also broadcast data. After that it will unicast data.

3.ROUTER

it is an intelligent device, having software. it unicast data. it integrate LAN and WAN. physically it is similar to switch. but it is much intelligent device as compared to switch.

4.BRIDGE

A bridge is a device used to connect the same type of network. for example similar local area network can be joined together to create larger area network.

Network Devices Domains

Bridge Switch RouterRouterHubHub

THANKS FOR PATIENCE

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