ZyXEL Communications MAX-207HW2, Руководство пользователя

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Chapter 6 The WIFI Configuration Screen
User’s Guide
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6.4.1 Additional Wireless Terms
The following table describes some wireless network terms and acronyms used in
the WiMAX Modem’s Web Configurator.
6.4.2 Wireless Security Overview
The following sections introduce different types of wireless security you can set up
in the wireless network.
6.4.2.1 SSID
Normally, the WiMAX Modem acts like a beacon and regularly broadcasts the SSID
in the area. You can hide the SSID instead, in which case the WiMAX Modem 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.
6.4.2.2 MAC Address Filter
Every device that can use a wireless network has a unique identification number,
called a MAC address.
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A MAC address is usually written using twelve hexadecimal
Table 23 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
WiMAX Modem. 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 WiMAX Modem.
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 WiMAX Modem does, it cannot
communicate with the WiMAX Modem.
Authentication The process of verifying whether a wireless device is allowed to use
the wireless network.
Fragmentation
Threshold A small fragmentation threshold is recommended for busy networks,
while a larger threshold provides faster performance if the network
is not very busy.