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SEMINAR ON SEMINAR ON Wi-Fi Wi-Fi

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Page 1: SEMINAR ON Wi-Fi. WHAT DOES Wi-Fi STANDS FOR? WHAT DOES Wi-Fi STANDS FOR? Wi-Fi Stands For Wireless Fidelity. Wi-Fi is a brand originally licensed by

SEMINAR ONSEMINAR ON

Wi-FiWi-Fi

Page 2: SEMINAR ON Wi-Fi. WHAT DOES Wi-Fi STANDS FOR? WHAT DOES Wi-Fi STANDS FOR? Wi-Fi Stands For Wireless Fidelity. Wi-Fi is a brand originally licensed by

WHAT DOES Wi-Fi STANDS FOR?WHAT DOES Wi-Fi STANDS FOR?

Wi-Fi Stands For Wi-Fi Stands For Wireless FidelityWireless Fidelity..

Wi-FiWi-Fi is a brand originally licensed is a brand originally licensed by the Wi-Fi Alliance to describe the by the Wi-Fi Alliance to describe the underlying technology of wireless underlying technology of wireless local area networks (WLAN) based on local area networks (WLAN) based on the IEEE 802.11 specifications.the IEEE 802.11 specifications.

Page 3: SEMINAR ON Wi-Fi. WHAT DOES Wi-Fi STANDS FOR? WHAT DOES Wi-Fi STANDS FOR? Wi-Fi Stands For Wireless Fidelity. Wi-Fi is a brand originally licensed by

HISTORY OF Wi-FiHISTORY OF Wi-FiThe precursor to Wi-Fi was invented in The precursor to Wi-Fi was invented in 1991 by NCR Corporation/AT&T in 1991 by NCR Corporation/AT&T in Nieuwegein, the NetherlandsNieuwegein, the Netherlands . .

It was initially intended for cashier It was initially intended for cashier systems.systems.

The first wireless products were brought The first wireless products were brought on the market under the name WaveLAN on the market under the name WaveLAN with speeds of 1 Mbit/s to 2 Mbit/s .with speeds of 1 Mbit/s to 2 Mbit/s .

Page 4: SEMINAR ON Wi-Fi. WHAT DOES Wi-Fi STANDS FOR? WHAT DOES Wi-Fi STANDS FOR? Wi-Fi Stands For Wireless Fidelity. Wi-Fi is a brand originally licensed by

How it worksHow it works????

The typical Wi-Fi setup contains one or more The typical Wi-Fi setup contains one or more Access Points (APs) and one or more clients.Access Points (APs) and one or more clients.

An AP broadcasts its SSID (Service Set An AP broadcasts its SSID (Service Set Identifier) via packets that are called Identifier) via packets that are called BEACONSBEACONS, which are broadcast every 100 , which are broadcast every 100 msms

The beacons are transmitted at 1 Mbit/s, and are The beacons are transmitted at 1 Mbit/s, and are of relatively short duration and therefore do not of relatively short duration and therefore do not have a significant influence on performance.have a significant influence on performance.

Page 5: SEMINAR ON Wi-Fi. WHAT DOES Wi-Fi STANDS FOR? WHAT DOES Wi-Fi STANDS FOR? Wi-Fi Stands For Wireless Fidelity. Wi-Fi is a brand originally licensed by

Based on the settings Based on the settings (e.g. the SSID), the (e.g. the SSID), the client may decide client may decide whether to connect to whether to connect to an AP. an AP.

Say two APs of the Say two APs of the same SSID are in same SSID are in range of the client, the range of the client, the firmware may decide firmware may decide based on signal based on signal strength to which of strength to which of the two APs it will the two APs it will connect.connect.

Page 6: SEMINAR ON Wi-Fi. WHAT DOES Wi-Fi STANDS FOR? WHAT DOES Wi-Fi STANDS FOR? Wi-Fi Stands For Wireless Fidelity. Wi-Fi is a brand originally licensed by

CHANNELSCHANNELS Wi-Fi uses the Wi-Fi uses the

spectrum near 2.4 spectrum near 2.4 GHz, which is GHz, which is standardized, standardized, Except for 802.11a, Except for 802.11a, which operates at which operates at 5 GHz.5 GHz.

Page 7: SEMINAR ON Wi-Fi. WHAT DOES Wi-Fi STANDS FOR? WHAT DOES Wi-Fi STANDS FOR? Wi-Fi Stands For Wireless Fidelity. Wi-Fi is a brand originally licensed by

Examples of Wi-Fi DevicesExamples of Wi-Fi Devices

Wireless Access Wireless Access Point (WAP)Point (WAP)

Wireless RoutersWireless Routers

Wireless Ethernet Wireless Ethernet BridgeBridge

Range ExtenderRange Extender

Page 8: SEMINAR ON Wi-Fi. WHAT DOES Wi-Fi STANDS FOR? WHAT DOES Wi-Fi STANDS FOR? Wi-Fi Stands For Wireless Fidelity. Wi-Fi is a brand originally licensed by

Wireless Access Point (WAP)Wireless Access Point (WAP)

A wireless access A wireless access point (AP) connects a point (AP) connects a group of wireless group of wireless stations to an stations to an adjacent wired local adjacent wired local area network (LAN). area network (LAN).

Page 9: SEMINAR ON Wi-Fi. WHAT DOES Wi-Fi STANDS FOR? WHAT DOES Wi-Fi STANDS FOR? Wi-Fi Stands For Wireless Fidelity. Wi-Fi is a brand originally licensed by

Wireless RoutersWireless Routers

A wireless router A wireless router connects a group of Wi-connects a group of Wi-Fi-enabled devices to an Fi-enabled devices to an adjacent wired network adjacent wired network (such as a cable modem (such as a cable modem or DSL modem). or DSL modem).

A wireless router is a A wireless router is a wireless access point wireless access point combined with an combined with an ethernet hub.ethernet hub.

Page 10: SEMINAR ON Wi-Fi. WHAT DOES Wi-Fi STANDS FOR? WHAT DOES Wi-Fi STANDS FOR? Wi-Fi Stands For Wireless Fidelity. Wi-Fi is a brand originally licensed by

Wireless Ethernet BridgeWireless Ethernet BridgeA wireless ethernet bridge connects two separate A wireless ethernet bridge connects two separate networksnetworks

Range ExtenderRange ExtenderA wireless range extender can increase the range A wireless range extender can increase the range of an existing wireless network by being of an existing wireless network by being strategically placed in locations where the wireless strategically placed in locations where the wireless router or access point signal is degraded or out of router or access point signal is degraded or out of range.range.

Page 11: SEMINAR ON Wi-Fi. WHAT DOES Wi-Fi STANDS FOR? WHAT DOES Wi-Fi STANDS FOR? Wi-Fi Stands For Wireless Fidelity. Wi-Fi is a brand originally licensed by

Advantages of Wi-FiAdvantages of Wi-Fi

Allows LANs to be deployed without Allows LANs to be deployed without cabling, typically reducing the costs of cabling, typically reducing the costs of network deployment and expansion.network deployment and expansion.

Wi-Fi networks support roaming, in which Wi-Fi networks support roaming, in which a mobile client station such as a laptop a mobile client station such as a laptop computer can move from one access computer can move from one access point to another as the user moves point to another as the user moves around a building or area. around a building or area.

Page 12: SEMINAR ON Wi-Fi. WHAT DOES Wi-Fi STANDS FOR? WHAT DOES Wi-Fi STANDS FOR? Wi-Fi Stands For Wireless Fidelity. Wi-Fi is a brand originally licensed by

Wi-Fi is a global set of standards. Wi-Fi is a global set of standards. Unlike cellular carriers, the same Wi-Unlike cellular carriers, the same Wi-Fi client works in different countries Fi client works in different countries around the world. around the world.

Widely available in more than Widely available in more than 250,000 public hot spots and millions 250,000 public hot spots and millions of homes and corporate and of homes and corporate and university campuses worldwideuniversity campuses worldwide

Page 13: SEMINAR ON Wi-Fi. WHAT DOES Wi-Fi STANDS FOR? WHAT DOES Wi-Fi STANDS FOR? Wi-Fi Stands For Wireless Fidelity. Wi-Fi is a brand originally licensed by

Disadvantages of Wi-FiDisadvantages of Wi-Fi

Spectrum assignments and operational Spectrum assignments and operational limitations are not consistent worldwidelimitations are not consistent worldwide

Power consumption is fairly high Power consumption is fairly high compared to some other standards, compared to some other standards, making battery life and heat a concernmaking battery life and heat a concern

Page 14: SEMINAR ON Wi-Fi. WHAT DOES Wi-Fi STANDS FOR? WHAT DOES Wi-Fi STANDS FOR? Wi-Fi Stands For Wireless Fidelity. Wi-Fi is a brand originally licensed by

Wi-Fi networks have limited range. Range Wi-Fi networks have limited range. Range also varies with frequency band, as WiFi is also varies with frequency band, as WiFi is no exception to the physics of radio wave no exception to the physics of radio wave propagation.propagation.

WiFi networks can be monitored and used WiFi networks can be monitored and used to read and copy data (including personal to read and copy data (including personal information) transmitted over the network information) transmitted over the network when no encryption such as VPN is usedwhen no encryption such as VPN is used

Page 15: SEMINAR ON Wi-Fi. WHAT DOES Wi-Fi STANDS FOR? WHAT DOES Wi-Fi STANDS FOR? Wi-Fi Stands For Wireless Fidelity. Wi-Fi is a brand originally licensed by

CONCLUSIONCONCLUSION

• Despite of some disadvantages Wi-Fi is Despite of some disadvantages Wi-Fi is driving into the future of networking.driving into the future of networking.

• It is also common for people to It is also common for people to unintentionally use others' Wi-Fi unintentionally use others' Wi-Fi networks without explicit authorization. networks without explicit authorization. Operating systems such as Windows XP Operating systems such as Windows XP and Mac OS X automatically connect to and Mac OS X automatically connect to an available wireless network, an available wireless network, depending on the network configuration.depending on the network configuration.

• It’s a technology we cannot live without.It’s a technology we cannot live without.