Transcript The Freedom of Wi-Fi - 123SeminarsOnly.com

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 possible
 Employees seat is not fixed
 Handling 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 802.11a
 Operates at 5 GHz (less popular)
 50-75 feet range
 More expensive,Not compatible with 802.11b
IEEE 802.11g
 Combine the feature of both standards (a,b)
 100-150 feet range
 2.4 GHz radio frequencies,Compatible with ‘b’
Elements of a WI-FI Network
1.Switch --- Nortel WLAN 2360
2.Access point --- NORTEL WLAN 2330
3.Devices --- Mobiles, Laptop, Personal computers
4.WIFI Cards--- PCMCIA Cards, PCI Cards
5.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
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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 Testing
2. 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
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Mobility
Ease of Installation
Flexibility
Cost
Reliability
Security
Use unlicensed part of the radio spectrum
Roaming
Speed
LIMITATIONS
 Interference
 Degradation in performance
 High power consumption
 Limited range
Wi-Fi Applications
 Home
 Small Businesses
 Large Corporations & Campuses
 Health Care
 Travellers