Alvarion BreezeACCESS VL System Manual page 214

Chapter 4 - Operation and Administration
advantage to units that need to transmit high priority traffic (depending also on
the configured values for the Contention Window parameters).
Other parameters related to transmission to the wireless media that can be
configured separately for high/low priority packets are the Number of HW Retries
and Burst Duration.
Typically, a lower value of Number of HW Retries should be configured for traffic
such as VoIP, which on the one hand is sensitive to delays and on the other hand
is less sensitive to missing packets than data traffic.
The Burst Duration, which defines the maximum duration of a burst, should be
set to a lower value for delay sensitive traffic. Typically the Burst Duration of the
AU should be set to higher value than that of the SUs, because of the higher
number of packets that should be transmitted by the AU.
When the Wireless Link Prioritization feature is enabled, the following parameters
are not applicable:
Arbitration Inter-Frame Spacing (AIFS)
Number of HW Retries
Burst Mode Option
Burst Mode Time Interval
When an SU with a SW version below 4.0 tries to associate with an AU that has
the Wireless Link Prioritization feature enable, the AU will generate a trap that
will include information about this SU. In this way the system administrator can
be alerted that the SU should be upgraded. This is necessary because otherwise
an SU that does not support the Wireless Link Prioritization feature will send all
the traffic as high priority.
CAUTION
Verify that all SUs served by an AU with the Wireless Link Prioritization Option enabled use a SW
version that supports this feature (SW version 4.0 and higher). Otherwise, overall performance and
quality of service in the cell may be reduced since all data from an SU with SW version below 4.0
will be sent with high priority.
The Wireless Link Prioritization Parameters menu includes the following:
4.2.6.6.3.5.1 Wireless Link Prioritization Option
The Wireless Link Prioritization Option enables or disables the Wireless Link
Prioritization feature.
The default option is Disable.
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BreezeACCESS VL System Manual