Brocade Mobility Access Point System Reference Guide (Supporting software release 5.5.0.0 and later) - Manual (Page 457)

Brocade Mobility Access Point System Reference Guide 447
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6. Configure the following parameters in respect to the WLAN’s intended Downstream Rate Limit,
or traffic from wireless clients to associated access point radios:
7. Set the following Downstream Random Early Detection Threshold settings for each access
category. An early random drop is conducted when a traffic stream falls below the set
threshold for the selected WLAN.
Enable Select this radio button to enable rate limiting for data transmitted from access point radios to
associated wireless clients. Enabling this option does not invoke rate limiting for data traffic in the
upstream direction. This feature is disabled by default.
Rate Define an upstream rate limit from 50 - 1,000,000 kbps.This limit constitutes a threshold for the
maximum the number of packets transmitted or received over the WLAN (from all access
categories). Traffic that exceeds the defined rate is dropped and a log message is generated. The
default setting is 5,000 kbps.
Maximum Burst Size Set a maximum burst size from 2 - 1024 kbytes. The smaller the burst, the less likely the
downstream packet transmission will result in congestion for the WLANs wireless client
destinations. By trending the typical number of ARP, broadcast, multicast and unknown unicast
packets over a period of time, the average rate for each access category can be obtained. Once a
baseline is obtained, administrators should then add a minimum of a 10% margin to allow for traffic
bursts at the site. The default burst size is 320 kbytes.
Background Traffic Set a percentage for WLAN background traffic in the downstream direction. This is a percentage of
the maximum burst size for low priority traffic. Background traffic exceeding the defined threshold
is dropped and a log message is generated. Background traffic consumes the least bandwidth of
any access category, so this value can be set to a lower value once a general downstream rate is
known by the network administrator (using a time trend analysis). The default threshold is 50%.
Best Effort Traffic Set a percentage for WLAN best effort traffic in the downstream direction. This is a percentage of
the maximum burst size for normal traffic. Best effort traffic exceeding the defined threshold is
dropped and a log message is generated. Best effort traffic consumes little bandwidth, so this
value can be set to a lower value once a general downstream rate is known by the network
administrator (using a time trend analysis). The default threshold is 50%.
Video Traffic Set a percentage for WLAN video traffic in the downstream direction. This is a percentage of the
maximum burst size for video traffic. Video traffic exceeding the defined threshold is dropped and a
log message is generated. Video traffic consumes significant bandwidth, so this value can be set to
a higher value once a general downstream rate is known by the network administrator (using a time
trend analysis). The default threshold is 25%.
Voice Traffic Set a percentage for WLAN voice traffic in the downstream direction. This is a percentage of the
maximum burst size for voice traffic. Voice traffic exceeding the defined threshold is dropped and a
log message is generated. Voice applications consume significant bandwidth, so this value can be
set to a higher value once a general upstream rate is known by the network administrator (using a
time trend analysis). The default threshold is 0%. 0% means no early random drops will occur.