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Anika Ohab ID:142-15-3568

Umme Habiba ID: 142-15-3677

Abul HasnathID:142-15-3532

Shahinur Rahman ID: 142-15-3606

Members

Introduction

Defination

Types

configuration

Advantage & Dis-Advantage

Application

Contents

A WIRELESS LOCAL AREA NETWORK(LAN) IS A FLEXIBLE

DATA COMMUNICATIONS SYSTEM IMPLEMENTED AS AN

EXTENSION TO, OR AS AN ALTERNATIVE FOR, A WIRED LAN.

• A wireless LAN or WLAN is a wireless local area network that

uses radio waves as its carrier.

• The last link with the users is wireless, to give a network

connection to all users in a building or campus.

• The backbone network usually uses cables

What??

• The wireless LAN connects to a wired

LAN

• There is a need of an access point that

bridges wireless LAN traffic into the

wired LAN.

• The access point (ap) can also act as a

repeater for wireless nodes, effectively

doubling the maximum possible distance

between nodes.

Topologies

HOW WIRELESS LANS WORKS:Wireless LANs operate in almost the same way as wired LANs, using the same networking

protocols and supporting the most of the same applications.

Works

COMPONENTS OF WIRELESS ARCHITECTURE:

Wireless LAN Architecture Is Composed Of Different Components Which Help In

Establishing The Local Area Network Between Different Operating Systems.

These Components Are Very Essential For Wi-fi Architecture.

• Access Point

• Clients

• Bridge

Access Points:A Special Type Of Routing Device That Is Used To Transmit The

Data Between Wired And Wireless Networking Device Is Called As AP.

Clients:Any Kind Of Device Such As Personal Computers, Note Books, Or Any

Kind Of Mobile Devices Which Are Inter Linked With Wireless Network Area

Referred As A Client Of Wireless LAN Architecture.

Bridge:A Special Type Of Connectors Which Is Used To Establish Connections

Between Wired Network Devices Such As Ethernet And Different Wireless

Networks Such As Wireless LAN. It Is Called As Bridge. .

HOW TO CONFIGURE WIRELESS LANS

• FIVE WAYS TO CONFIGURE A WIRELESS LAN

• PEER-TO-PEER NETWORK

• CLIENT AND ACCESS POINT

• MULTIPLE ACCESS POINTS AND ROAMING

• USING AN EXTENSION POINT

• USING A DIRECTIONAL ANTENNA

A BASIC WIRELESS PEER TO PEER NETWORK

• Two Pcs Equipped With Wireless Adapter

Cards Can Be Set Up As An Independent

Network Whenever They Are Within Range

Of One Another.

Requires no

administration or

configuration.

Each client has access

to only the resources

shared by the other

client and not to a

central server.

IEEE 802.11 WIRELESS LAN STANDARD

• In Response To Lacking Standards, IEEE Developed The First Internationally

Recognized Wireless LAN Standard – IEEE 802.11

• IEEE Published 802.11 In 1997, After Seven Years Of Work

• Most Prominent Specification For WLANS

• Scope Of IEEE 802.11 Is Limited To Physical And Data Link Layers.

802.11 Networks Can Be Used In Two

Modes:

1. Infrastructure And

2. Ad Hoc Mode

Types

Infrastructure Mode Requires

A Central Access Point That

All Devices Connect To.

Ad-hoc Mode Is Also Known As

“Peer-to-peer” Mode.

Ad-hoc Networks Don't

Require A Centralized Access

Point.

Instead, Devices On The

Wireless Network Connect

Directly To Each

MAC Layer Covers Three Functional Areas:

IEEE 802.11 Medium Access Control:

MAC

1.Reliable Data Delivery

2.Access Control

3.Security

When Employing Wireless Transmission, This Has The

Disadvantage That It Is Relatively Easy To Listen In To Any

Data Transferred. This Is Why We Need To Be Encrypted.

There Are Different Encryption Methods In Existence.

ENCRYPTION

WEP

Wired Equivalent

Privacy was the first

encryption key

protocol.

• it is no longer

considered safe

and is relatively

easy to hack.

• This is why we

should no longer

use it.

WPA

WiFi Protected Access

has been developed from

the WEP protocol.

• Improved security

mechanisms provide

better protection.

• a dynamic key was

introduced for the

purpose of transfers.

WPA2

WPA2 builds on WPA

But employs the strong AES

algorithm to encode the data

transfer.

• WI-FI OR WIFI Is A Technology That Allows Electronic Devices To Connect To

A Wireless LAN (WLAN) Network.

• The Range Of A Residential Wi-fi Network Depends On

1.The Wireless Access Point (WAP) Or Wireless Router

2.Its' Antenna(s) Sensitivity, As Well As

3.The Exact 802.11 Standard Being Used

Range

A general rule of thumb in home networking says that 802.11b/g WAPs and routers

support a range of up to 150 feet (46 m) indoors and 300 feet (92 m) outdoors.

Another rule of thumb holds that the effective range of 802.11a is approximately

one-third that of 802.11b/g.

Obstructions in home such as brick walls and metal frames or siding

can greatly reduce the range of a Wi-Fi LAN by 25% or more.

FUTURE OF WLAN:

• WLANS MOVE TO MATURITY

• HIGHER SPEEDS

• IMPROVED SECURITY

• BETTER ERROR CONTROL

• LONG DISTANCES

• NEW VENDORS

• GLOBAL NETWORKING

ANYWHERE, ANYTIME, ANY-FORM CONNECTIVITY…

Future!

Mobility:The Primary Advantage Of Wireless Technology.

Having This Freedom Of Being Able To Move Around

Without Wires Being Connected.

Ease And Cost Of Installation :Need To Have To Run Cables Through

Walls And Ceilings Is Eliminated With A Wireless LAN.

Easier Network Modifications

Increased Network Reliability :One Of The Most Common Network

Problems Is Having Cable Failures.

Advantage

Speedier Disaster Recovery :If Primary Operations Go Down, Having A

WLAN Makes Life Easier. Allowing Ability For Network To Be Up And Running

So Fast Without Business Being Significantly Disturbed.

Radio Signal Interference :wireless Devices Operate In The Same Radio

Frequency As Other Devices. Signals From Other Devices Can Disrupt Wireless

Transmissions, Or A WLAN Device Can Interfere With Other Devices.

Security :the Wireless Signal Is Broadcast In Open Air Making Security A Big

Concern. Security Has Improved For WLAN But It Remains A Major Issue And

Must Be Properly Addressed.

DISADVANTAGE OF WLAN

1.HEALTH RISK

• Being A Health Risk Is A Ongoing Issue. Wireless Devices Emit Low Levels Of

RF. It Is A Know Fact That High Levels Of RF With Heating Effects Can Cause

Biological Damage.

2.COSTWireless Network Cards Cost 4 Times More Than Wired Network Cards.

• The Access Points Are More Expensive Than Hubs And Wires.

3.SIGNAL BLEED OVER

• Access Points Pick Up The Signals Of Adjacent Access Points Or Overpower

Their Signal.

4.ENVIRONMENTAL CONDITIONS

• Susceptible To Weather And Solar Activity.

• Constrained By Buildings, Trees, Terrain.

WIRELESS LAN APPLICATIONS:

•

MEDICAL PROFESSIONALS

CORPORATE

EDUCATION

TEMPORARY SITUATIONS

AIRLINES

SECURITY STAFF

EMERGENCY CENTERS

Applications