wireless fidelity full report

[seminar class]

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Wireless Fidelity
What is the goal of 802.11 standard ?
 To develop a Medium Access Control (MAC) and Physical Layer (PHY) specification for wireless connectivity for fixed, portable and moving stations within a local area.
802.11 sub-standards(amendments ) ….
 802.11 MAC (Media Access Control) ratified 1999
 802.11b PHY 2.4 GHz (max 11 Mbps) ratified 1999
 802.11a PHY 5.0 GHz (max 54 Mbps) ratified 1999
 802.11g PHY 2.0 GHz (max 54 Mbps) ratified 2003
 802.11i Security draft number XXX
 802.11e QoS, Multimedia draft number XXX
 802.11h European regulations for 5GHz draft number XXX
 802.11h Japan regulations for 5GHz draft number XXX
Do I need any license to use 802.11 device ?
 No , 2.4 GHz and 5.0 GHz are public available frequency !!!
Context with OSI layers
Logical Link Control Services
Standard 802.11 frame format
Frames types and subtypes
 Three types of frames:
 Control
(ACK,RTS,CTS ,Power Save …)
 Management
(Beacon,Probe Request ,Probe Response,
Association request , Association response …)
 Data
(Data, Null Data, Data_CF_Ack , ….)
Infrastructure Model includes: (most common)
• Stations (STA)
– any wireless device
• Access Point (AP)
– connects BSS to DS
– controls access by STA’s
• Basic Service Set (BSS)
– a region controlled by an AP
– mobility is supported within a single BSS
• Extended Service Set (ESS)
– a set of BSS’s forming a virtual BSS
– mobility is supported between BSS’s in an ESS
• Distribution Service (DS) connection between BSS’s