Chapter 7 Wireless LAN
7.9.2 Additional Wireless Terms
The following table describes some wireless network terms and acronyms used in the ZyXEL Device’s Web Configurator.
Table 26 Additional Wireless Terms
TERM | DESCRIPTION |
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. |
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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. |
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|
Authentication | The process of verifying whether a wireless device is allowed to use |
| the wireless network. |
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Fragmentation | A small fragmentation threshold is recommended for busy networks, |
Threshold | while a larger threshold provides faster performance if the network |
| is not very busy. |
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7.9.3 Wireless Security Overview
The following sections introduce different types of wireless security you can set up in the wireless network.
7.9.3.1 SSID
Normally, the ZyXEL Device acts like a beacon and regularly broadcasts the SSID in the area. You can hide the SSID instead, in which case the ZyXEL Device does not broadcast the SSID. In addition, you should change the default SSID to something that is difficult to guess.
This type of security is fairly weak, however, because there are ways for unauthorized wireless devices to get the SSID. In addition, unauthorized wireless devices can still see the information that is sent in the wireless network.
7.9.3.2 MAC Address Filter
Every device that can use a wireless network has a unique identification number, called a MAC address.1 A MAC address is usually written using twelve hexadecimal
96 |
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