MSM7xx Controllers Configuration Guide v6.4.0

The QoS feature defines four traffic queues based on the Wi-Fi Multimedia (WMM) access
categories. In order of priority, these queues are:
Typically used forWMM access categoryQueue
Voice trafficAC_VO1
Video trafficAC_VI2
Best effort data trafficAC_BE3
Background data trafficAC_BK4
Outgoing wireless traffic on the VSC is assigned to a queue based on the selected priority
mechanism. Traffic delivery is based on strict priority (per the WMM standard). Therefore, if
excessive traffic is present on queues 1 or 2, it will reduce the flow of traffic on queue 3 and queue
4.
Regardless of the priority mechanism that is selected:
• Traffic that cannot be classified by a priority mechanism is assigned to queue 3.
• SVP (SpectraLink Voice Protocol) traffic is always assigned to queue 1, except if you select
the VSC-based priority mechanism, in which case SVP traffic is assigned to the configured
queue.
Priority mechanisms
Priority mechanisms are used to classify traffic on the VSC and assign it to the appropriate queue.
The following mechanisms are available:
802.1p
This mechanism classifies traffic based on the value of the VLAN priority field present within the
VLAN header.
802.1p (VLAN priority field value)Queue
6, 71
4, 52
0, 33
1, 24
VSC-based priority
This mechanism is unique to HP. It enables you to assign a single priority level to all traffic on a
VSC. If you enable the VSC-based priority mechanism, it takes precedence regardless of the priority
140 Working with VSCs