PRESENTATION ON WI-FI TECHNOLOGY

Contents• Need of WIFI• Introduction• Wi-Fi Technologies• Wi-Fi Network Elements• Wi-Fi Architecture• How a Wi-Fi Network Works• Wi-Fi Network Topologies• Wi-Fi Security• Post Implementation• Advantages/ Disadvantages of Wi-Fi• Applications

NEED ????

Higher authorities do not want wiring When guest/auditor comes then installation

of new LAN is not possibleEmployees seat is not fixedHandling of cables(wires) is difficult

Introduction• Wireless Technology is an alternative to Wired Technology,

• Wi-Fi Network connect computers to each other, to the internet and to the wired network.

The Wi-Fi Technology

Wi-Fi Networks use Radio Technologies to transmit & receive data at high speed:

• IEEE 802.11b• IEEE 802.11a• IEEE 802.11g

IEEE 802.11b • Operates at 2.4GHz radio spectrum• 100 -150 feet range• Most popular, Least Expensive

IEEE 802.11aOperates at 5 GHz (less popular) 50-75 feet rangeMore expensive,Not compatible with

802.11b

IEEE 802.11g

Combine the feature of both standards (a,b)

100-150 feet range2.4 GHz radio frequencies,Compatible

with ‘b’

Elements of a WI-FI Network1.Switch --- Nortel WLAN 23602.Access point --- NORTEL WLAN 23303.Devices --- Mobiles, Laptop, Personal computers4.WIFI Cards--- PCMCIA Cards, PCI Cards5.Safeguards--- Antivirus & Firewalls

WI FI Architecture

How a Wi-Fi Network Works• Basic concept is same as Walkie talkies.• A Wi-Fi hotspot is created by installing an access

point to an internet connection.• An access point acts as a base station. • When Wi-Fi enabled device encounters a hotspot the

device can then connect to that network wirelessly.• A single access point can support up to 30 users and

can function within a range of 100 – 150 feet indoors and up to 300 feet outdoors.

• Many access points can be connected to each other via Ethernet cables to create a single large network.

How are Multiple Transmitters Supported ?• Carrier Sense Medium Access with

collision avoidance protocol (CSMA/CA)• Listen before talking• Avoid collision by explicit Acknowledgement

(ACK)• Problem: additional overhead of ACK packets,

so slow performance

Wi-Fi Network Topologies

• AP-based topology

• Peer-to-peer topology

• Point-to-multipoint bridge topology

AP-based topology

• The client communicate through Access Point.

Peer-to-peer topology

• AP is not required.• Client devices within a cell can communicate

directly with each other.• It is useful for setting up of a wireless

network quickly and easily.

Point-to-multipoint bridge topology

This is used to connect a LAN in one building to a LANs in other buildings even if the buildings are miles apart. These conditions receive a clear line of sight between buildings.

WI-FI Security

The requirements for Wi-Fi network security can be broken down into two primary components:

Authentication User Authentication Server Authentication

Privacy

WI-FI Security Techniques

• Service Set Identifier (SSID)

• Wired Equivalent Privacy (WEP)

• 802.1X Access Control

• Wireless Protected Access (WPA)

• IEEE 802.11i

Post Implementation Test

There are basically two types of testing to be done

1. QTR-WEB Testing2. QTR-GUEST Testing

QTR-WEB Testing

Step1:Click on Wireless icon on the Taskbar

Step 2: Below shown window will appear, click on Refresh network list.

Step 3:

Double click on QTR-Web WI-FI Connection.

Step 4: Insert the Authentication Key Step 5: Wait for few moments, while it is accruing the IP address

Step 6: After acquiring the IP address it will show the connected as shown below

Step 7:Now try to open any link it will redirect to the authentication page put user domain login ID and Password

Step 8: Click on Yes on the below Security alert

Step 9: It will be authenticated if below message will be shown on the web screen.

Advantages

Mobility Ease of InstallationFlexibilityCostReliabilitySecurityUse unlicensed part of the radio spectrumRoamingSpeed

LIMITATIONS

InterferenceDegradation in performanceHigh power consumptionLimited range

Wi-Fi Applications

HomeSmall BusinessesLarge Corporations & CampusesHealth CareTravellers