ZyXEL Communications AG-225H User Manual
password approach makes WPA-PSK susceptible to brute-force password-guessing attacks but it’s still an
improvement over WEP as it employs an easier-to-use, consistent, single, alphanumeric password.
improvement over WEP as it employs an easier-to-use, consistent, single, alphanumeric password.
2.2.4 WPA-PSK/WPA2-PSK Application Example
A WPA-PSK application looks as follows.
Step 1.
First enter identical passwords into the AP and all wireless clients. The Pre-Shared Key (PSK)
must consist of between 8 and 63 ASCII characters (including spaces and symbols).
must consist of between 8 and 63 ASCII characters (including spaces and symbols).
Step 2.
The AP checks each client’s password and (only) allows it to join the network if it matches its
password.
password.
Step 3.
The AP derives and distributes keys to the wireless clients.
Step 4.
The AP and wireless clients use the TKIP encryption process to encrypt data exchanged
between them.
between them.
Figure 2-7
WPA-PSK/WPA2-PSK Authentication
2.2.5 WPA/WPA2
with
RADIUS Application Example
You need the IP address of the RADIUS server, its port number (default is 1812), and the RADIUS shared
secret. A WPA/WPA2 application example with an external RADIUS server looks as follows. “A” is the
RADIUS server. “DS” is the distribution system.
secret. A WPA/WPA2 application example with an external RADIUS server looks as follows. “A” is the
RADIUS server. “DS” is the distribution system.
Step 1.
The AP passes the wireless client’s authentication request to the RADIUS server.
Step 2.
The RADIUS server then checks the user's identification against its database and grants or
denies network access accordingly.
denies network access accordingly.
Step 3.
The RADIUS server distributes a Pairwise Master Key (PMK) key to the AP that then sets up a
key hierarchy and management system, using the pair-wise key to dynamically generate unique
key hierarchy and management system, using the pair-wise key to dynamically generate unique
WLAN Networking
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