Motorola AP-51XX - Manual (Page 208)

AP-51xx Access Point Product Reference Guide 5-60
5. Refer to the QBSS Load Element Setting field to optionally allow the access point to
communicate channel usage data to associated devices and define the beacon interval used
for channel utilization transmissions. The QBSS load represents the percentage of time the
channel is in use by the access point and its station count. This information is very helpful
in assessing the access point’s overall load on the channel, its availability for additional
device associations and multi media traffic support.
Select the Enable QBSS load element checkbox (its selected by default) to enable the
access point to communicate channel usage to MUs. Access points with high channel usage
may not be able to process real-time traffic effectively. Therefore, VOIP phones can use the
QBSS value to determine whether a different access point association can provide better
wireless support, since the QBSS network load is reduced as additional access points are
added.
If QBSS is enabled, define a QBSS Beacon Interval to define the beacon time (in seconds)
the access point uses to broadcast channel utilization information. This information should
be periodically accessed, as the access point’s network load will fluctuate throughout the
day.
6. Configure the Performance field to set the preamble, thresholds values 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.