ZyXEL nbg-334sh Manuel D’Utilisation

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 Chapter 5 Wireless LAN
ZyXEL NBG-334SH User’s Guide
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If your AP does not provide a local user database and if you do not have a RADIUS server, 
you cannot set up user names and passwords for your users.
Unauthorized devices can still see the information that is sent in the wireless network, even if 
they cannot use the wireless network. Furthermore, there are ways for unauthorized wireless 
users to get a valid user name and password. Then, they can use that user name and password 
to use the wireless network.
Local user databases also have an additional limitation that is explained in the next section.
5.2.4  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 user 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 WEP
WPA-PSK, or WPA2-PSK.
Usually, you should set up the strongest encryption that every wireless client in the wireless 
network supports. For example, suppose the AP does not have a local user database, and you 
do not have a RADIUS server. Therefore, there is no user authentication. Suppose the wireless 
network has two wireless clients. Device A only supports WEP, and device B supports WEP 
and WPA. Therefore, you should set up Static WEP in the wireless network.
"
It is recommended that wireless networks use WPA-PSKWPA, or stronger 
encryption. IEEE 802.1x and WEP encryption are better than none at all, but it 
is still possible for unauthorized devices to figure out the original information 
pretty quickly.
It is not possible to use WPA-PSKWPA or stronger encryption with a local 
user database. In this case, it is better to set up stronger encryption with no 
authentication than to set up weaker encryption with the local user database.
Table 21   Types of Encryption for Each Type of Authentication
NO AUTHENTICATION
RADIUS SERVER
Weakest
No Security
WPA
Static WEP
WPA-PSK
Strongest
WPA2-PSK
WPA2