ZyXEL Router Prestige 662HW-61 91-004-371001 Manual Do Utilizador

Prestige 662H/HW Series User’s Guide

Chapter 8 Wireless LAN Setup

100

By generating unique data encryption keys for every data packet and by creating an integrity 
checking mechanism (MIC), TKIP makes it much more difficult to decode data on a Wi-Fi 
network than WEP, making it difficult for an intruder to break into the network. 

The encryption mechanisms used for WPA and WPA-PSK are the same. The only difference 
between the two is that WPA-PSK uses a simple common password, instead of user-specific 
credentials. The common-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.

A WPA-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 (including spaces and 
symbols).

2 The AP checks each client’s password and (only) allows it to join the network if it 

matches its password.

3 The AP derives and distributes keys to the wireless clients.

4 The AP and wireless clients use the TKIP encryption process to encrypt data exchanged 

between them.

Figure 29   WPA - PSK Authentication

You need the IP address of the RADIUS server, its port number (default is 1812), and the 
RADIUS shared secret. A WPA 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.