Chapter 4 Wireless LAN

4.4.1 WMM QoS

WMM (Wi-Fi MultiMedia) QoS (Quality of Service) ensures quality of service in wireless networks. It controls WLAN transmission priority on packets to be transmitted over the wireless network.

WMM QoS prioritizes wireless traffic according to delivery requirements. WMM QoS is a part of the IEEE 802.11e QoS enhancement to certified Wi-Fi wireless networks.

On APs without WMM QoS, all traffic streams are given the same access priority 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.

The ZyXEL Device uses WMM QoS to prioritize traffic streams according to the IEEE 802.1q tag or DSCP information in each packet’s header. The ZyXEL Device automatically determines the priority to use for an individual traffic stream. This prevents reductions in data transmission for applications that are sensitive to latency (delay) and jitter (variations in delay).

4.4.1.1 WMM QoS Priorities

The following table describes the WMM QoS priority levels that the ZyXEL Device uses.

Table 9 WMM QoS Priorities

PRIORITY LEVEL

DESCRIPTION

voice

Typically used for traffic that is especially sensitive to jitter. Use this priority

(WMM_VOICE)

to reduce latency for improved voice quality.

 

 

video

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

(WMM_VIDEO)

prioritized over other data traffic.

 

 

best effort

Typically used for traffic from applications or devices that lack QoS

(WMM_BEST_EFFORT)

capabilities. Use best effort priority for traffic that is less sensitive to latency,

 

but is affected by long delays, such as Internet surfing.

background

This is typically used for non-critical traffic such as bulk transfers and print

(WMM_BACKGROUND)

jobs that are allowed but that should not affect other applications and users.

 

Use background priority for applications that do not have strict latency and

 

throughput requirements.

 

 

4.5General Wireless LAN Screen

"If you are configuring the ZyXEL Device from a computer connected to the wireless LAN and you change the ZyXEL Device’s SSID, channel or security settings, you will lose your wireless connection when you press Apply to confirm. You must then change the wireless settings of your computer to match the ZyXEL Device’s new settings.

Click Network > Wireless LAN to open the General screen.

 

53

PLA-450 User’s Guide