ZyXEL Communications P-2608HWL-Dx Series 用户手册

P-2608HWL-Dx Series User’s Guide

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Chapter 9 Wireless LAN

Many types of encryption use a key to protect the information in the wireless network. The 
longer the key, the stronger the encryption. Every device in the wireless network must have 
the same key.

With ZyXEL’s OTIST, you set up the SSID and the encryption (WEP or WPA-PSK) on the 
ZyXEL Device. Then, the ZyXEL Device transfers them to the devices in the wireless 
networks. As a result, you do not have to set up the SSID and encryption on every device in 
the wireless network.

The devices in the wireless network have to support OTIST, and they have to be in range of 
the ZyXEL Device when you activate it. See 

 for more details.

The following sections introduce different ways to improve the performance of the wireless 
network.

You can turn on Wi-Fi MultiMedia (WMM) QoS to improve the performance of voice and 
video applications in the wireless network. QoS gives high priority to voice and video, which 
makes them run more smoothly. Similarly, it gives low priority to many large file downloads 
so that they do not reduce the quality of other applications.

The following table describes wireless network terms and acronyms used in the ZyXEL 
Device.

RTS/CTS Threshold

In a wireless network which covers a large area, wireless devices are 

sometimes not aware of each other’s presence.  This may cause them to send 

information to the AP at the same time and result in information colliding and 

not getting through.
By setting this value lower than the default value, the wireless devices must 

sometimes get permission to send information to the ZyXEL Device. The lower 

the value, the more often the devices must get permission.
If this value is greater than the fragmentation threshold value (see below), then 

wireless devices never have to get permission to send information to the 

ZyXEL Device.

Preamble

A preamble affects the timing in your wireless network. There are two 

preamble modes: long and short.

 

If a device uses a different preamble mode 

than the ZyXEL Device does, it cannot communicate with the ZyXEL Device.