ZyXEL nbg-334w Guia Do Utilizador

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Chapter 5 Wireless LAN
NBG334W User’s Guide
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5.2.3  User Authentication
You can make every user log in to the wireless network before they can use it. This is called 
user authentication. However, every wireless client in the wireless network has to support 
IEEE 802.1x to do this.
For wireless networks, there are two typical places to store the user names and passwords for 
each user.
• In the AP: this feature is called a local user database or a local database.
• In a RADIUS server: this is a server used in businesses more than in homes.
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.
Table 25   Types of Encryption for Each Type of Authentication
NO AUTHENTICATION
RADIUS SERVER
Weakest
No Security
WPA
Static WEP
WPA-PSK
Strongest
WPA2-PSK
WPA2