ZyXEL Communications AMG1302 Manual Do Utilizador

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 Chapter 7 Wireless LAN
AMG1302/AMG1202-TSeries User’s Guide
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7.10.3.4  Encryption
Wireless networks can use encryption to protect the information that is sent in the wireless 
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 
 for information about this.)
For example, if the wireless network has a RADIUS server, you can choose WPA or WPA2. If users 
do not log in to the wireless network, you can choose no encryption, Static WEPWPA-PSK, or 
WPA2-PSK.
Usually, you should set up the strongest encryption that every device in the wireless network 
supports. For example, suppose you have a wireless network with the AMG1302/AMG1202-TSeries 
and you do not have a RADIUS server. Therefore, there is no authentication. Suppose the wireless 
network has two devices. Device A only supports WEP, and device B supports WEP and WPA-PSK. 
Therefore, you should set up Static WEP in the wireless network.
Note: It is recommended that wireless networks use WPA-PSKWPA, or stronger 
encryption. The other types of encryption are better than none at all, but it is still 
possible for unauthorized wireless devices to figure out the original information 
pretty quickly.
When you select WPA2 or WPA2-PSK in your AMG1302/AMG1202-TSeries, you can also select an 
option (WPA compatible) to support WPA as well. In this case, if some of the devices support WPA 
and some support WPA2, you should set up WPA2-PSK or WPA2 (depending on the type of 
wireless network login) and select the WPA compatible option in the AMG1302/AMG1202-TSeries.
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.
7.10.4  Signal Problems
Because wireless 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 29   
Types of Encryption for Each Type of Authentication
NO AUTHENTICATION
RADIUS SERVER
Weakest
No Security
WPA
Static WEP
WPA-PSK
Strongest
WPA2-PSK
WPA2