Wireless communication involves the transfer of information over a distance without wires. Marconi invented the wireless telegraph in 1896, enabling communication across the Atlantic Ocean. Advances led to voice communication by radio in 1914 and communication satellites in the 1960s. There are four main types of wireless networks: WLANs covering small areas like buildings, WPANs with short range, WMANs spanning a city, and WWANs with worldwide but lower performance coverage. Wireless communication provides mobility, easier installation, increased reliability and disaster recovery but also risks of interference and potential health issues from high radio frequencies. Security methods include WEP, SSID, and MAC address filtering.
2. INTRODUCTION
• Wireless communication is the transfer of information over a
distance without the use of electrical conductors or wires.
• The distances involved may be short (a few meters as in
television remote control) or long (thousands or millions of
kilometers for radio communications)
3. History of wireless communication
• Marconi invented the wireless telegraph in 1896
• Communication by encoding alphanumeric characters in
analog signal
• Sent telegraphic signals across the Atlantic Ocean
• 1914 – first voice communication over radio waves
• Communications satellites launched in 1960s
• Advances in wireless technology
• Radio, television, mobile telephone, communication
satellites
4. Types of Wireless Networks
a) WLANS: Wireless Local Area Networks
b) WPANS: Wireless Personal Area Networks
c) WMANS: Wireless Metropolitan Area Networks
d) WWANS: Wireless Wide Area Networks
5. Type Coverage Performance Standards
Wireless PAN
Within reach of a
person
Moderate
Wireless PAN Within reach
of a person Moderate
Bluetooth, IEEE 802.15,
and IrDa Cable replacement
for peripherals
Wireless LAN
Within a building or
campus
High
IEEE 802.11, Wi-Fi, and
HiperLAN
Wireless MAN Within a city High IEEE 802.16
Wireless WAN Worldwide Low Cellular 2G, 2.5G, and 3G
Comparison of Wireless Network Types
6. Advantages of wireless
communication
• Mobility
• Easier and less expensive installation
• Increased reliability
• Network cable failures may be the most common source of
network problems
• Disaster recovery
• In the event of a disaster, managers can quickly relocate the
office
7. Disadvantages of wireless
communication
• Radio signal interference
• The potential for two types of signal interference exists
• Health risks
• High levels of RF can produce biological damage through
heating effects
8. Security methods for wireless
communication
1. WEP (Wired Equivalent Privacy)
stop the interception of radio frequency signals by
unauthorized users
2. SSID (Service Set Identifier)
SSID acts a simple password by allowing a WLAN
network to be split up into different networks each having a
unique identifier.
3. MAC (Media Access Control) address filtering
A list of MAC addresses belonging to the client
computers can be inputted into an Access Point and thus
only those computers will be allowed access.