Technology

Elements
How a Wi-Fi Network Works
Wi-Fi Network Topologies
Wi-Fi

Configurations
Applications of Wi-Fi
Advantages/ Disadvantages of Wi-Fi

to Wired Technology, which is commonly used, for connecting devices

in wireless mode.

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.

use Radio Technologies to transmit & receive data at high

speed :

IEEE 802.11b
IEEE 802.11a
IEEE 802.11g

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.

GHz (less popular)
54 Mbps (theoretical speed)

15-20 Mbps (Actual speed)
50-75 feet range
More expensive
Not compatible with 802.11b

of both standards (a,b)
100-150 feet range
54

Mbps Speed
2.4 GHz radio frequencies
Compatible with ‘b’

The AP is a wireless LAN transceiver or “base station”

that can connect one or many wireless devices simultaneously to the Internet.

Wi-Fi cards - They accept the wireless signal and relay information.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.

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.

topology (Ad-hoc Mode)

Point-to-multipoint bridge topology

BSA-RF coverage provided by an AP.
ESA-It

consists of 2 or more BSA.
ESA cell includes 10-15% overlap to allow
roaming.

within a cell can communicate directly

with each other.
It is useful for setting up of a wireless network quickly
and easily.

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. The line-of-sight range varies based on the type of wireless bridge and antenna used as well as the environmental conditions.

Large Corporations & Campuses
Health Care
Wireless ISP

(WISP)
Travellers

Cost
Reliability
Security
Use unlicensed part

of the radio spectrum
Roaming
Speed is high.

consumption
Limited range