Hamdard University BangladeshHamdard Nagar, Gazaria, Munshiganj
IEEE 802.11 Project
Presentation Outline
Introduction Architecture MAC Sublayer Distribution Coordination Function Point Coordination Function MAC Layer Frame Physical Layer IEEE 802.11 FHSS IEEE 802.11 DSSS IEEE 802.11 Infrared
2/13
Introduction of IEEE 802.11
Released in 1997Define the specification for wireless LAN.Covers physical and data-link layer.
3/13
Architecture
Define two kinds of services.
4/13
MAC Sub-layer
5/13
Distribution Coordination FunctionIf a station has MAC frame to transmit, it listens to the medium.
If the medium is idle, station may transmit.Otherwise it must wait until current transmission is complete.
6/13
Data
SourceDestination
Point Coordination Function
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Implemented in infrastructure network.Use repetition interval.
NAV
Polled Station
Oth
ers
Repetition Interval
Contention-free
MAC Layer Frame
8/13
framecontrol duration address
1address
2address
4address
3 payload FCS
2 2 6 6 6 2 6 0 - 2312 4sequence
control
Type FromDSSubtype To
DSMore frag WEPMore
dataPower
mgtRetry RsvdProtocolversion
2 2 4 1 1 1 1 1 11 1
Physical Layer
9/13
IEEE 802.11 Frequency-Hopping Spread Spectrum
10/13
IEEE 802.11 Direct-Sequence Spread Spectrum
11/13
12/13
IEEE 802.11 Infrared
Thanks To All
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