ZyXEL Communications NWA3550 ユーザーズマニュアル

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Chapter 8 Wireless Security Configuration
NWA3550 User’s Guide
110
8.1.3  User Authentication
Authentication is the process of verifying whether a wireless device is allowed to use the 
wireless network. You can make every user log in to the wireless network before they can use 
it. However, every device in the wireless network has to support IEEE 802.1x to do this.
For wireless 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 wireless 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.
8.1.4  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 security, 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 ZyXEL Device 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. Therefore, you should set up WEP in the wireless network.
"
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.
Table 24   Types of Encryption for Each Type of Authentication
NO AUTHENTICATION
RADIUS SERVER
Weakest
No Security
WPA
Static WEP
WPA-PSK
Strongest
WPA2-PSK
WPA2