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Introduction Components of Wi-Fi and its working IEEE 802.11 Architecture Advantages and...
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Transcript of Introduction Components of Wi-Fi and its working IEEE 802.11 Architecture Advantages and...
Wireless Fidelity
P r e s e n t e d B y :
Naila Habib Khan
Introduction
Components of Wi-Fi and its working
IEEE 802.11 Architecture
Advantages and Limitations
Topics
The term Wi-Fi is often used as a synonym for wireless LAN(WLAN).
A wireless network uses radio waves, just like cell phones, televisions and radios
do.
Uses high frequency radio waves rather than wires to communicate between
nodes.
Wi-Fi is a generic term that refers to the IEEE 802.11 standard.
What Is Wi-Fi?
A global association of companies, promotes WLAN technology and
certifies products if they conform to certain standards of
interoperability.
Not every IEEE 802.11-compliant device is submitted for certification
to the Wi-Fi Alliance, sometimes because of costs associated with
the certification process.
The Wi-Fi Alliance
It means that products from different companies will work together, so
users don't get locked into a single brand of Wi-Fi products.
Wi-Fi Alliance member companies can submit products for certification.
Wi-Fi CERTIFIED products will contain a logo identifying which features
have been tested and that the product has met all the standards of the
notation.
Interoperability
The Wi-Fi Technology
Year Data Transfer
Frenqency
IEEE 802.11 1997 2 Mbps 2.4 GHzUnregulated
IEEE 802.11b 1999 11 Mbps 2.4 GHzUnregulated
IEEE 802.11a 1999-2000 54 Mbps 5GHzRegulated
IEEE 802.11g 2002-2003 54 Mbps 2.4 GHz
Introduction
Components of Wi-Fi and its working
IEEE 802.11 Architecture
Advantages and Limitations
Topics
The AP is a wireless LAN transceiver or “base station” that can connect
one or many wireless devices simultaneously to the Internet.
Access Point (AP)
They accept the wireless signal. They can be internal and external.
(e.g PCMCIA Card for Laptop and PCI Card for Desktop PC)
Safeguards Firewalls and anti-virus software protect networks from uninvited users
and keep information secure
Wi-Fi cards
How a Wi-Fi Network Works A Wi-Fi hotspot is created by installing an access point to an internet
connection.
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 up to 300 feet.
It’s a two-way radio communication.
A computer's wireless adapter translates data into a radio signal and
transmits it using an antenna.
A wireless router receives the signal and decodes it. The router sends
the information to the Internet using a physical, wired Ethernet
connection.
The process also works in reverse….
Wi-Fi communication
Topics Introduction
Components of Wi-Fi and its working
IEEE 802.11 Architecture
Advantages and Limitations
IEEE 802.11 defines three types of stations based on their mobility in a
wireless LAN
No transition mobility-Station is stationary or move only inside a BSS
BSS transition mobility-Station can move from one BSS to another but
confined inside one ESS
ESS transition mobility-station can move from one ESS to another. How
ever there is no guarantee that the communication is continuous during
the move.
Station/Node Types
Topics
Introduction
Components of Wi-Fi and its working
IEEE 802.11 Architecture
Advantages and Limitations
Advantages
Long-Term Cost Savings
Reduced Installation Time
Mobility
Scalability
Easy access to the Internet in public places
Limitations OR Disadvantages
Interference
Degradation in performance
High power consumption
Limited range