Symbol AP-51xx, Product Reference Manual, Page: 204 / 622

AP-51xx Access Point Product Reference Guide 5-60
5. Configure the Performance field to set the preamble, thresholds values, data rates and
QoS values for the radio.
Support Short
Preamble The preamble is approximately 8 bytes of packet header generated
by the
access point
and attached to the packet prior to
transmission from the 802.11b radio. The preamble length for
802.11b transmissions is data rate dependant. The short preamble
is 50% shorter than the long preamble. Leave the checkbox
unselected if in a mixed MU/AP environment, as MUs and the
access point
are required to have the same RF Preamble settings
for interoperability. The default is Disabled. The preamble length
for 802.11a and 802.11g transmissions is the same, with no long or
short preamble lengths.
RTS Threshold RTS allows the
access point
to use RTS (Request To Send) on
frames longer than the specified length. The default is 2341bytes.
Set RF QoS Click the Set RF QoS button to display the Set RF QOS screen to
set QoS parameters for the radio. Do not confuse with the QoS
configuration screen used for a WLAN. The Set RF QoS screen
initially appears with default values displayed.
Select
manual from the Select Parameter set drop-down menu
to edit the CW min and CW max (contention window), AIFSN
(Arbitrary Inter-Frame Space Number) and TXOPs Time for each
Access Category. These are the QoS policies for the 802.11a or
802.11b/g radio, not the QoS policies configured for the WLAN (as
created or edited from the
Quality of Service Configuration
screen).
Symbol recommends only advanced users manually set these
values. If the type of data-traffic is known, use the drop-down
menu to select a
11g-wifi, 11b-wifi, 11g-default, 11b-default ,
11g-voice or
11b-voice
option. Wifi represents multimedia
traffic, default is typical data traffic and voice is for “Voice-Over-IP”
supported wireless devices.
Click OK to implement the selected QoS values and return to the
802.11a or 802.11b/g radio configuration screen. Clicking Cancel
reverts the screen to the last saved configuration.