Quality of Service (QoS)

Extreme Networks ExtremeWireless solution provides advanced Quality of Service (QoS) management to provide better network traffic flow. Such techniques include:

• WMM (Wi-Fi Multimedia) — WMM is enabled per WLAN service. The controller provides centralized management of the AP features. For devices with WMM enabled, the standard provides multimedia enhancements for audio, video, and voice applications. WMM shortens the time between transmitting packets for higher priority traffic. WMM is part of the 802.11e standard for QoS. In the context of the ExtremeWireless Solution, the ToS/DSCP field is used for classification and proper class of service mapping, output queue selection, and priority tagging.
• IP ToS (Type of Service) or DSCP (Diffserv Codepoint) — The ToS/DSCP field in the IP header of a frame indicates the priority and class of service for each frame. Adaptive QoS ensures correct priority handling of client payload packets tunneled between the controller and AP by copying the IP ToS/DSCP setting from client packet to the header of the encapsulating tunnel packet.
• Rate Control — Rate Control for user traffic can also be considered as an aspect of QoS. As part of Role definition, the user can specify (default) role that includes Ingress and Egress rate control. Ingress rate control applies to traffic generated by wireless clients and Egress rate control applies to traffic targeting specific wireless clients. The bit-rates can be configured as part of globally available profiles which can be used by any particular configuration. A global default is also defined.

Quality of Service (QoS) management is also provided by:

• Assigning high priority to a WLAN service
• Adaptive QoS (automatic and all time feature)
• Support for legacy devices that use SpectraLink Voice Protocol (SVP) for prioritizing voice traffic (configurable)