ZyXEL Communications G-570S, Руководство пользователя

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Appendix D Wireless LANs
ZyXEL G-570S User’s Guide
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Wireless Client WPA Supplicants
A wireless client supplicant is the software that runs on an operating system instructing the
wireless client how to use WPA. At the time of writing, the most widely available supplicant is
the
WPA patch for Windows XP, Funk Software's Odyssey client.
The Windows XP patch is a free download that adds WPA capability to Windows XP's built-in
"Zero Configuration" wireless client. However, you must run Windows XP to use it.
WPA(2) 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(2) application example with an external RADIUS server
looks as follows. "A" is the RADIUS server. "DS" is the distribution system.
1 The AP passes the wireless client's authentication request to the RADIUS server.
2 The RADIUS server then checks the user's identification against its database and grants
or denies network access accordingly.
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 data encryption keys to encrypt every data packet that is wirelessly
communicated between the AP and the wireless clients.
Figure 95 WPA(2) with RADIUS Application Example
WPA(2)-PSK Application Example
A WPA(2)-PSK application looks as follows.
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 or 64 hexadecimal characters
(including spaces and symbols).
2 The AP checks each wireless client's password and (only) allows it to join the network if
the password matches.
3 The AP and wireless clients use the pre-shared key to generate a common PMK
(Pairwise Master Key).