ZyXEL Communications G-270S Network Card User Manual


 
ZyXEL G-270S User’s Guide
Chapter 2 Wireless LAN Network 27
2.2.2.1 EAP Authentication
EAP (Extensible Authentication Protocol) is an authentication protocol that runs on top of the
IEEE 802.1x transport mechanism in order to support multiple types of user authentication. By
using EAP to interact with an EAP-compatible RADIUS server, an access point helps a
wireless station and a RADIUS server perform authentication.
The type of authentication you use depends on the RADIUS server and an intermediary AP(s)
that supports IEEE 802.1x. The ZyXEL G-270S supports EAP-TLS and EAP-PEAP. Refer to
Appendix D on page 75 for descriptions.
For EAP-TLS authentication type, you must first have a wired connection to the network and
obtain the certificate(s) from a certificate authority (CA). A certificate (also called digital IDs)
can be used to authenticate users and a CA issues certificates and guarantees the identity of
each certificate owner.
2.2.3 WPA(2)
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.
2.2.3.1 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(2)-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.