D-Link DWC-1000 User Manual page 70

Wireless Controller
Radi o 2 s upports :
DTIM Peri od: Th e Deliv ery Traffic In fo rmat io n M ap (DTIM ) mes s age is an
elemen t in clu d ed in s o me
B eacon frames . It in d icat es wh ich clien t s tatio ns, cu rrent ly s leepin g in lo w -
p o wer mo d e, h av e d at a b uffered o n t h e acces s p o in t await in g p ick -u p . Th e
DTIM p erio d y o u s p ecify in d icat es h o w o ft e n t h e clien t s s erv ed b y t h is
acces s p o int s hou ld ch eck fo r b u ffered d ata s till o n t h e A P await in g p icku p .
Sp ecify a DTIM p erio d wit h in t h e g iv en ran g e (1 – 255). Th e meas u remen t is
in b eaco n s . Fo r examp le, if y o u s et t h is field t o 1, clien t s will ch eck fo r
b u ffered d at a o n t h e A P at ev ery b eaco n . If y o u s et t h is field t o 10, clien t s
will ch eck o n ev ery 10t h b eaco n .
B eacon Interval : Beaco n frames are t ran s mit t ed b y an acces s p o in t at
reg u lar in t erv als t o an n o u n ce t h e exis t en ce o f t h e wireles s n et wo rk. Th e
d efau lt b eh avio r is t o s end a b eaco n frame o n ce ev ery 100 millis eco n d s (o r
h ig h er t h ro u ghp ut wh en it d o es n o t n eed t o b e co mp at ib le wit h leg acy
d ev ices (802.11b / g o r 802.11a).
• IEEE 802.11b / g o p erat es in t h e 2.4 GHz ISM b an d . IEEE 802.11b is
an en h an cemen t o f t h e in it ial 802.11 PHY t o in clu d e 5.5 M b p s an d 11
M b p s d at a rat es . It u s es d irect s eq u en ce s p read s p ect ru m (DSSS) o r
freq u en cy h o pp ing s p read s p ect ru m (FHSS ) as well as co mp lemen t ary
co d e key in g (CCK) t o p ro v id e t h e h ig h er d at a rat es . It s u p p o rt s d at a
rat es ran g in g fro m 1 t o 11 M b p s . IEEE 802.11g is a h ig h er s p eed
ext en s io n (u p t o 54 M b p s ) t o t h e 802.11b PHY. It u s es o rt h o g o n al
freq u en cy d iv is ion mu lt ip lexin g (OFDM ). It s u p p orts d at a rat es ran ging
fro m 1 t o 54 M b p s .
• IEEE 802.11b / g / n o p erat es in t h e 2.4 GHz ISM b an d an d in clu d es
s u p p o rt fo r 802.11b , 802.11g , an d 802.11n d ev ices .
• 2.4 GHz IEEE 802.11n is t h e reco mmen d ed mo d e fo r n et wo rks wit h
802.11n d ev ices t hat o p erat e in t h e 2.4 GHz freq u en cy t hat d o n o t n eed
t o s u p p o rt 802.11a o r 802.11b / g d ev ices . IEEE 802.11n can ach iev e a
h ig h er t h ro u ghp ut wh en it d o es n o t n eed t o b e co mp at ib le wit h leg acy
d ev ices (802.11b / g o r 802.11a).
68
User Manual