Contents
Contents
1. Basic CSMA/CA operation
1. Basic CSMA/CA operation
2. Wireless medium access example
2. Wireless medium access example
3. Usage of RTS / CTS
3. Usage of RTS / CTS
4. Fragmentation
4. Fragmentation
!"
##
$ %#
& '#()
* +#,-.
"!-.
#
1. Basic CSMA/CA operation
$
-,
))
!"
##
$ ,-.
& %#
* '#(
/ 01#012
"
!-.,#
1. Basic CSMA/CA operation
!
. Here is Infrastructure
basic service set (BSS).
. All stations and AP
have equal priority
transmission in
downlink (from the AP)
and uplink (from a
station) is similar.
"
3-
4
1. Basic CSMA/CA operation
'5 '5
2
!01
%
#01!
#,(6!
-62#,-6
'##
(2,
)+)-
+#
1. Basic CSMA/CA operation
$
'5 '5 '5
2
!01
%
#01!
6758'582
%9#,
#9'5
9#
#)
#
9#
1. Basic CSMA/CA operation
&
'5 '5 '5
2
!01
%
#01!
%#6"
4)6
:66-::
9#
1. Basic CSMA/CA operation
*
'5 '5 '5
2
!01
%
#01!
4)6
'))4;<#)
#,6
#6
9#
'#,
6##
4;<
1. Basic CSMA/CA operation
/
%#6'5'5"
'5'#0=µ>µ
'55'#0/=µ&*µ
)(
#'5#
'5'('56)'5
?=$,
?=$,
?=$6
?=$6
1. Basic CSMA/CA operation
>
'5 '5 '5
2
%
#
:
:6
':,
#,:#
:
6
9#
%
6:
@A
1. Basic CSMA/CA operation
B
'5 '5
%
#
:
:66:
,#C6C+%%6(
#6(
2
2
6
'5
1. Basic CSMA/CA operation
:
4D4D
) $ & *
5
E"/,:,#
%9,A
##)
:%
# A(
,6
1. Basic CSMA/CA operation
?
'5 '5 1'5
2
!01
%
#01!
#,
#1'5#E,
01)
9#
#)
'5
1. Basic CSMA/CA operation
F
'5 '5 '5
2
!01
%
#01!
#,)01
,-.,#
#+G9H
9
#
,)
#
!-.
1. Basic CSMA/CA operation
,-.01
!E66
,(6-
01I
!
'5
I
2
1. Basic CSMA/CA operation
!-.01,,)
66,-.,!-.
(6#, A(
#6
,6
!
'5
,6
,
!-.
+6
,-.
2
1. Basic CSMA/CA operation
#?=$,
'#####,
(,#
#,
'5
H
0$
5
@0&0$=
µ
'
'5
H
0$
6
@0>&
'5
0$
10
@0
=$&
/#
"
H
?=$,
?=$,
1. Basic CSMA/CA operation
#?=$6
'#?=$6( 6/%
Fµ%,-.#?=$6,)#
#?=$,
'5
H
0$
4
@0/0F
µ
'
'5
H
0$
5
@0&
'5
0$
10
@0
=$&
>#
"
H
?=$6
?=$6
1. Basic CSMA/CA operation
#,-.
5, 0/&H=$&,-.,
#),#),
,=H
-)#,(
%9%9
#"(!(C6-C
C8'582C7,-.),
1. Basic CSMA/CA operation
!
'5
#
#
!-.
6-(
!
-(,
#8,-.
$CC
,-.9E
6-
$
2
2. Wireless medium access example
$
!
'5 '5
#
&
-
*;(
!
CC
6
-
&
*
2
2. Wireless medium access example
&
!
'5
/
6-
'5
/
2
2. Wireless medium access example
#)H
'5 '5 '5
2
!01
%
#01!
9
#
01!
!-.
#(
,-.-)#CC
,)66#(#6
#6
2. Wireless medium access example
3. Usage of RTS & CTS
%+%%+7%
6JC,"
4
$
;,"
$CC4
,
01
'# -( $
01I