ZyXEL Communications G-570U, User Manual

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ZyXEL G-570U User’s Guide
76 Chapter 6 Wireless Screens
To use Dynamic WEP, enable and configure the RADIUS server and enable Dynamic WEP
Key Exchange in the
WIRELESS Security 802.1x screen. Ensure that the wireless station’s
EAP type is configured to one of the following:
• EAP-TLS
• EAP-TTLS
• PEAP
Note: EAP-MD5 cannot be used with Dynamic WEP Key Exchange.
6.10 Introduction to WPA and WPA2
Wi-Fi Protected Access (WPA) is a subset of the IEEE 802.11i standard. WPA2 (IEEE
802.11i) is a wireless security standard that defines stronger encryption, authentication and
key management than WPA.
Key differences between WPA(2) and WEP are improved data encryption and user
authentication.
If both an AP and the wireless clients support WPA2 and you have an external RADIUS
server, use WPA2 for stronger data encryption. If you don't have an external RADIUS server,
you should use WPA2-PSK (WPA2-Pre-Shared Key) that only requires a single (identical)
password entered into each access point, wireless gateway and wireless client. As long as the
passwords match, a wireless client will be granted access to a WLAN.
If the AP or the wireless clients do not support WPA2, just use WPA or WPA-PSK depending
on whether you have an external RADIUS server or not.
Select WEP only when the AP and/or wireless clients do not support WPA or WPA2. WEP is
less secure than WPA or WPA2.
6.10.1 Encryption
Both WPA and WPA2 improve data encryption by using Temporal Key Integrity Protocol
(TKIP), Message Integrity Check (MIC) and IEEE 802.1x. In addition to TKIP, WPA2 also
uses Advanced Encryption Standard (AES) in the Counter mode with Cipher block chaining
Message authentication code Protocol (CCMP) to offer stronger encryption.
The encryption mechanisms used for WPA(2) and WPA(2)-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(2)-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.