P-662H/HW-D Series User’s Guide

7.8 WMM QoS

WMM (Wi-Fi MultiMedia) QoS (Quality of Service) ensures quality of service in wireless networks for multimedia applications.

WMM allows you to prioritize wireless traffic according to the delivery requirements of the individual and applications.

WMM is a part of the IEEE 802.11e QoS enhancement to certified Wi-Fi wireless networks.

7.8.1 WMM QoS Example

When WMM QoS is not enabled, all traffic streams are given the same access throughput to the wireless network. If the introduction of another traffic stream creates a data transmission demand that exceeds the current network capacity, then the new traffic stream reduces the throughput of the other traffic streams.

When WMM QoS is enabled, the streams are prioritized according to the needs of the application. You can assign different priorities to different applications. This prevents reductions in data transmission for applications that are sensitive.

7.8.2 WMM QoS Priorities

The following table describes the priorities that you can apply to traffic that the ZyXEL Device sends to the wireless network.

Table 45 WMM QoS Priorities

PRIORITY LEVELS:

Highest

Typically used for voice traffic or video that is especially sensitive to jitter

 

(variations in delay). Use the highest priority to reduce latency for improved

 

voice quality.

High

Typically used for video traffic which has some tolerance for jitter but needs to

 

be prioritized over other data traffic.

Mid

Typically used for traffic from applications or devices that lack QoS

 

capabilities. Use mid priority for traffic that is less sensitive to latency, but is

 

affected by long delays, such as Internet surfing.

Low

This is typically used for non-critical “background” traffic such as bulk transfers

 

and print jobs that are allowed but that should not affect other applications and

 

users. Use low priority for applications that do not have strict latency and

 

throughput requirements.

Chapter 7 Wireless LAN

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