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ATHENA Chapter 16: Wireless LAN Objective  What is Wireless LAN?  What is infrastructure Mode?  What is ad-hoc mode?  IEEE 802.11a,802.11b,802.11g ATHENA WireLess Lan  Wireless Lan connect the computers and network communication devices within geographically limited areas.  WireLess Lan use frequency band 2,4Ghz ATHENA Wireless Lan ATHENA  WireLess Lan does not require: • Lining-up • Line of sight Wireless Lan  WireLess Lan has many advantages in connecting the devices together in your office. • Fast deployment. ATHENA • Easy installation,easy and convenient to operate. • Easy upgarde and maintenance. • Network access everywhere,everytime. Wireless Lan  IEEE 802.11 : Defined network standards for physical components of wireless Lan  IEEE 802.11 : built in 1997 ATHENA Wireless Lan  IEEE 802.11 has two modes: ATHENA • Infrastructure mode • Ad-hoc mode Wireless Lan  Infrastructure ATHENA mode: • Wireless Lan use Access-point • And computers with wireless Card are connected together through Access Point Wireless Lan Ad-hoc ATHENA mode: • Devices which can connect together directly • Without Access point Wireless Lan IEEE 802.11b : •Wireless Lan –Speed: 1Mbps – 11Mbps –Frequency Band : 2,4 Ghz ISM Band(Insdustrial Scientific Medical Band) ATHENA Wireless Lan  ATHENA IEEE 802.11b Plus (IEEE 802.11b +) • Improved from IEEE 802.11 b • Frequence band : 2,4Ghz DSSS • Speed :22 Mbps Wireless Lan  ATHENA IEEE 802.11 a: • Wireless Lan. – Speed : 6Mbps – 54 Mbps – Frequence band : 5Ghz or more Wireless Lan  ATHENA IEEE 802.11a is : • Not compatible with 802.11b and 802.11b Plus Wireless Lan  IEEE 802.11g is : -Wireless Lan – Speed : 1Mbps – 54 Mbps – Compatible with 802.11b and 802.11a ATHENA Wireless Lan  ATHENA Wireless : • IEEE 802.11a,IEEE 802.11b, IEEE 802.11b plus, IEEE 802.11 g use Access method CSMA/CD(Carrier Sense Multiple Access/Collision Detection) Wireless Lan  Components of Wireless ATHENA • Wireless Access Point • Wireless LAN PCI Card • Wireless LAN PCMCIA Card/Carbus • Wireless Print Server Wireless Lan  ATHENA Wireless Access Point • Similar Hub/Switch in Wireline • Connect clients use frequence band : 2,4Ghz-2,4835Ghz • Distance from access point to wireless client: depend on environment , devices, standard of network( IEEE 802.11a, IEEE 802.11b ….) Wireless LAN  ATHENA Wireless Access Point Wireless Lan  ATHENA Wireless LAN PCI Card • Net card for destop computer • PCI • Operate on many channels Wireless Lan ATHENA Wireless LAN PCI card ATHENA Wireless Lan Wireless LAN PCMCIA Card/CarBus • Net card for Notebook/Laptop • PCMCIA Wireless Lan ATHENA Wireless LAN PCMCIA card/Carbus Wireless Lan ATHENA Wireless Print Server • Devices which share printer in wireless LAN Wireless Lan Wireless ATHENA Print Server Wireless Lan ATHENA Wireless Lan ATHENA Wireless Lan ATHENA Wireless Lan ATHENA The roaming process is seamless and transparent to the user. Wireless Lan ATHENA Access Point as Repeater Summary  Ad-hoc Mode  Infrastructure Mode  IEEE 802.11a,802.11b,802.11g ATHENA