Configuring quality of service 431
Nortel WLAN—Security Switch 2300 Series Configuration Guide

Bandwidth Management for QoS

You can configure maximum bandwidth (full duplex rate) for aggregates of access categories (ACs) for a wireless client.
Downstream packets are shaped and upstream packets are policed. The AP has one queue per AC and each queue is a
finite size (<100 packets). If the network to AP flow exceeds the determined rate, the AP queue overflows and packets
are sent to the AP radio AC queues independently. The VoIP queue is given more transmit opportunities and therefore
empties faster than other queues. To configure this feature, use the following command:
WSS# set qos-profile profile-name max-bw max-bw-kb
The max-bw-kb attribute is a value between 1 and 100,000 Kbps.
If you configure SSID medium time weights, you will guarantee a minimum service level to specific service profiles on
a radio. Medium time weights determine the relative transmit utilization of the radio between service profiles. You can
configure the weight from 1 to 100 with 100 as the sum of all configured weights.
To configure SSID medium weights, use the following command:
WSS# set radio-profile profile-name weighted-fair-queuing mode [enable|disable] weight
service-profile-weight
You can configure SSID bandwidth limits to restrict traffic through a service profile. The configured limit is full duplex
in increments of Kbps and is only enforced on a transmitted packets. SSID weights do not restrict bandwidth unless the
radio is congested. Hence, you may select SSID bandwidth limits over SSID weights as bandwidth limits effectively
place a measurable cap on bandwidth through the AP uplink. To configure maximum bandwidth per SSID, use the
following command:
WSS# set service-profile <profile-name> max-bw [max-bw-kb]

SVP QoS mode

The SVP QoS mode optimizes forwarding of SVP traffic by setting the random wait time an AP
radio waits before transmitting the traffic to 0 microseconds.
Normally, an AP radio waits an additional number of microseconds following the fixed wait time,
before forwarding a queued packet or frame. Each forwarding queue has a different range of
possible random wait times. The Voice queue has the narrowest range, whereas the Background and
Best Effort queues have the widest range. The random wait times ensure that the Voice queue gets
statistically more access to the air than the other queues.
By setting the random wait time to 0 for SVP, the SVP QoS mode provides SVP traffic the greatest
possible access to the air, on a statistical basis. The QoS mode affects forwarding of SVP traffic only.
The random wait times for other types of traffic are the same as those used when the QoS mode is
WMM.