HAL Id: inria-00072441
https://hal.inria.fr/inria-00072441
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An Efficient Simulation Model for Wireless LANs Applied to the IEEE 802.11 Standard
Paul Mühlethaler, Najid Abdellah
To cite this version:
Paul Mühlethaler, Najid Abdellah. An Efficient Simulation Model for Wireless LANs Applied to the IEEE 802.11 Standard. [Research Report] RR-4182, INRIA. 2001. �inria-00072441�
ISRN INRIA/RR--4182--FR+ENG
a p p o r t
d e r e c h e r c h e
INSTITUT NATIONAL DE RECHERCHE EN INFORMATIQUE ET EN AUTOMATIQUE
An efficient simulation model for wireless LANs applied to the IEEE 802.11 standard
Paul M¨uhlethaler , Abdellah Najid
No 4182
Avril 2001
TH `EME 1
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Station C
DIFS
Station B Station A Frame
Station C Frame
Station B Frame
DIFS
Defer Defer
Collision window Decremented back-off Remaining back-off
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Other
Collision window
Source Frame
Ack SIFS
Defer
Destination
DIFS DIFS
DIFS = Distributed Interframe spacing SIFS = Short Interframe spacing
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Data
Other Collision window
Src
Dest
DIFS DIFS
DIFS = Distributed Interframe spacing SIFS = Short Interframe spacing
Ack RTS
CTS
SIFS SIFS
NAV (RTS) NAV (CTS)
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start of transmission at the source
node
Start of carrier sense
detection in other nodes
collision window Another alien transmission can start in the the collision window creating a collision
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Event end of backoff
The carrier sense turns to busy due to another scheduled
transmission
Carrier sense idle
New event end of backoff start of a
backoff
The event backoff is suppressed
9'µq`ynf :˵eq`±o t«{r¢{
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Other
Collision window
Source Frame Ack
SIFS
Defer
Destination
DIFS DIFS
DIFS = Distributed Interframe spacing SIFS = Short Interframe spacing
Added
"virtual"
transmision duration
9'µq`ynf :˵eq`±o t«{r¢e³{T`f ´{yt«cf=oÁT{Q®µf`rfefPtp¸
start of transmission at the source
node
start of carrier sense detection in other nodes
end of transmission at the source
node
collision window e
end of carrier in other
nodes
9Lq`ynf? :À{µmn{³`ftwf t«{rVµ/twc`fmwµeq`±o t«{r
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