Resolution
Typically, networks operate on a best-effort delivery basis. This means that all traffic has equal priority and an equal chance of being delivered in a timely manner. When congestion occurs, all traffic has an equal chance of being dropped. When the Quality of Service (QoS) feature is configured on the Cisco Access Point (AP), preferential treatment can be provided to certain traffic. Without QoS, the AP offers best-effort service to each packet, regardless of the packet contents or size. The AP sends the packets without any assurance of reliability, delay bounds, or throughput. With QoS configured on the AP, users are able to prioritize specific network traffic, and use congestion-management and congestion-avoidance techniques to provide preferential treatment. QoS implementation in a wireless LAN makes network performance more predictable and bandwidth utilization more effective. When QoS is configured, QoS policies are created and applied to the VLANS confgured on the AP. If VLANs are not used on the network, QoS policies can be applied to the AP Ethernet and radio ports.
For more information, refer to these documents:
Problem Type
Configure / Configuration issues
Products
Access point
Product OS
IOS