Wi-Fi Network Elements
How a Wi-Fi Network Works
Advantages and Limitations of Wi-Fi
• Wireless Technology is an alternative to Wired Technology,
which is commonly used, for connecting devices in wireless
• Wi-Fi (Wireless Fidelity) is a generic term that refers to the
IEEE 802.11 communications standard for Wireless Local
Area Networks (WLANs).
• Wi-Fi Network connect computers to each other, to the
internet and to the wired network.
• Wi-Fi works on physical and data link layer.
4. THE Wi-Fi TECHNOLOGY
Wi-Fi Networks use Radio Technologies to transmit &
receive data at high speed :
5. IEEE 802.11b
Appeared in late 1999
Operates at 2.4GHz radio spectrum
11 Mbps (theoretical speed) - within 30 m Range
4-6 Mbps (actual speed)
100 -150 feet range
Most popular, Least Expensive
Interference from mobile phones and Bluetooth devices which
can reduce the transmission speed.
6. IEEE 802.11a
Introduced in 2001
Operates at 5 GHz (less popular)
54 Mbps (theoretical speed)
15-20 Mbps (Actual speed)
50-75 feet range
Not compatible with 802.11b
7. IEEE 802.11g
Introduced in 2003
Combine the feature of both standards (a,b)
100-150 feet range
54 Mbps Speed
2.4 GHz radio frequencies
Compatible with ‘b’
10. Elements of a Wi-Fi Network
Access Point (AP) - The AP is a wireless LAN
transceiver or “base station” that can connect one or
many wireless devices in the same time to the Internet.
Safeguards - Firewalls and anti-virus software protect
networks from uninvited users and keep information
Wi-Fi cards (Adapters) - They accept the wireless
signal and relay information. They can be internal and
11. PCI and USB adapters
PCI adapter USB adapter
For Desktop For Laptop
12. How a Wi-Fi Network Works
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.
14. WI-FI APPLICATIONS
Large Corporations & Campuses
Wireless ISP (WISP)
15. Advantages of Wi-Fi
No Wires - A truly wireless networking solution.
No Waiting - Fast, easy deployments.
No Worries - A wireless networking system that is
secure, easy to manage, and built to grow with you.
Ease of Installation - Quick, easy setup.
Security - Many Types Of
Fast data transfer rates
16. Limitations of Wi-Fi
Interference from other devices : such as
telephones, microwave ovens.
High power consumption :making battery life and
heat a concern .
Data security risks :a huge challenge for Wi-Fi
17. Basic Wi-Fi Security Techniques
WEP(Wired Equivalent Privacy) : The original encryption
technique specified by the IEEE 802.11 standard.
WPA(Wi-Fi Protected Access ): A new standard that
provides improved encryption security over WEP.
WPA2 : is an improved version of WPA that uses
Advanced Encryption Standard (AES) technology.
18. Basic Wi-Fi Security Techniques(cont.)
Security Level Notes
WEP RC4 encryption
No longer used; it is can be
WPA TKIP Protocol High
encryption security over
WPA2 CCMP Protocol Very High
An improved version of
WPA that uses Advanced
Wi-Fi is a simple, cost-effective way to connect to the
Internet, without the need to physically connecting wires.
In 1997 IEEE drafted the 802.11 standard for wireless
local area networking.
Hotspot is a geographic area setup in any public
location, and has a readily accessible wireless network.
Security is a huge challenge for Wi-Fi Networks, many
Security Techniques are used to improve it.
Wi-Fi Networks have a several limitations that should be