ZyXEL Communications LTE7461-M602, User Manual

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Chapter 6 Wireless
LTE7461-M602 User’s Guide
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6.7.3.3 User Authentication
Authentication is the process of verifying whether a WiFi device is allowed to use the WiFi network. You
can make every user log in to the WiFi network before using it. However, every device in the WiFi
network has to support IEEE 802.1x to do this.
For WiFi networks, you can store the user names and passwords for each user in a RADIUS server. This is a
server used in businesses more than in homes. If you do not have a RADIUS server, you cannot set up user
names and passwords for your users.
Unauthorized WiFi devices can still see the information that is sent in the WiFi network, even if they
cannot use the WiFi network. Furthermore, there are ways for unauthorized WiFi users to get a valid user
name and password. Then, they can use that user name and password to use the WiFi network.
6.7.3.4 Encryption
WiFi networks can use encryption to protect the information that is sent in the WiFi network. Encryption is
like a secret code. If you do not know the secret code, you cannot understand the message.
The types of encryption you can choose depend on the type of authentication. (See Section 6.7.3.3 on
page 56 for information about this.)
For example, if the WiFi network has a RADIUS server, you can choose WPA or WPA2 . If users do not log in
to the WiFi network, you can choose no encryption, WPA-PSK , or WPA2-PSK .
Note: It is recommended that WiFi networks use WPA-PSK , WPA , or stronger encryption. The
other types of encryption are better than none at all, but it is still possible for
unauthorized WiFi devices to figure out the original information pretty quickly.
Many types of encryption use a key to protect the information in the WiFi network. The longer the key,
the stronger the encryption. Every device in the WiFi network must have the same key.
6.7.4 Signal Problems
Because WiFi networks are radio networks, their signals are subject to limitations of distance, interference
and absorption.
Problems with distance occur when the two radios are too far apart. Problems with interference occur
when other radio waves interrupt the data signal. Interference may come from other radio
transmissions, such as military or air traffic control communications, or from machines that are
coincidental emitters such as electric motors or microwaves. Problems with absorption occur when
physical objects (such as thick walls) are between the two radios, muffling the signal.
Table 21 Types of Encryption for Each Type of Authentication
NO AUTHENTICATION RADIUS SERVER
Weakest WPA No Security
WPA2
WPA-PSK
Strongest WPA2-PSK