Chapter 6 Wireless
LTE7461-M602 User’s Guide
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• Every device in the same WiFi network must use security compatible with the AP.
Security stops unauthorized devices from using the WiFi network. It can also protect the information
that is sent in the WiFi network.
Radio Channels
In the radio spectrum, there are certain frequency bands allocated for unlicensed, civilian use. For the
purposes of WiFi networking, these bands are divided into numerous channels. This allows a variety of
networks to exist in the same place without interfering with one another. When you create a network,
you must select a channel to use.
Since the available unlicensed spectrum varies from one country to another, the number of available
channels also varies.
6.7.2 Additional Wireless Terms
The following table describes some WiFi network terms and acronyms used in the Zyxel Device’s Web
Configurator.
6.7.3 WiFi Security Overview
By their nature, radio communications are simple to intercept. For WiFi data networks, this means that
anyone within range of a WiFi network without security can not only read the data passing over the
airwaves, but also join the network. Once an unauthorized person has access to the network, he or she
can steal information or introduce malware (malicious software) intended to compromise the network.
For these reasons, a variety of security systems have been developed to ensure that only authorized
people can use a WiFi data network, or understand the data carried on it.
These security standards do two things. First, they authenticate. This means that only people presenting
the right credentials (often a username and password, or a “key” phrase) can access the network.
Second, they encrypt. This means that the information sent over the air is encoded. Only people with
the code key can understand the information, and only people who have been authenticated are
given the code key.
Table 20 Additional WiFi Terms
TERM
DESCRIPTION
In a WiFi network which covers a large area, WiFi devices are sometimes not aware of
RTS/CTS Threshold
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 WiFi 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 WiFi
devices never have to get permission to send information to the Zyxel Device.
A preamble affects the timing in your WiFi network. There are two preamble modes: long
Preamble
and short.
If a device uses a different preamble mode than the Zyxel Device does, it
cannot communicate with the Zyxel Device.
The process of verifying whether a WiFi device is allowed to use the WiFi network.
Authentication
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.
