D-Link DAP-2590 - AirPremier N Dual Band PoE Access Point User Manual page 32

Section  - Configuration
Priority: When the Enable Priority check box is checked at the top of this window, this drop-down menu is used to select a priority
between 0 and 7.
WMM (Wi-Fi
Select Enable to provide basic Quality of Service features.
Multimedia):
D-Link DAP-590 User Manual