ZyXEL Communications VWG1312-B10A, User Manual

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Appendix D Wireless LANs
VMG1312-B10A User’s Guide
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EAP-TTLS (Tunneled Transport Layer Service)
EAP-TTLS is an extension of the EAP-TLS authentication that uses certificates for only the server-
side authentications to establish a secure connection. Client authentication is then done by sending
username and password through the secure connection, thus client identity is protected. For client
authentication, EAP-TTLS supports EAP methods and legacy authentication methods such as PAP,
CHAP, MS-CHAP and MS-CHAP v2.
PEAP (Protected EAP)
Like EAP-TTLS, server-side certificate authentication is used to establish a secure connection, then
use simple username and password methods through the secured connection to authenticate the
clients, thus hiding client identity. However, PEAP only supports EAP methods, such as EAP-MD5,
EAP-MSCHAPv2 and EAP-GTC (EAP-Generic Token Card), for client authentication. EAP-GTC is
implemented only by Cisco.
LEAP
LEAP (Lightweight Extensible Authentication Protocol) is a Cisco implementation of IEEE 802.1x.
Dynamic WEP Key Exchange
The AP maps a unique key that is generated with the RADIUS server. This key expires when the
wireless connection times out, disconnects or reauthentication times out. A new WEP key is
generated each time reauthentication is performed.
If this feature is enabled, it is not necessary to configure a default encryption key in the wireless
security configuration screen. You may still configure and store keys, but they will not be used while
dynamic WEP is enabled.
Note: EAP-MD5 cannot be used with Dynamic WEP Key Exchange
For added security, certificate-based authentications (EAP-TLS, EAP-TTLS and PEAP) use dynamic
keys for data encryption. They are often deployed in corporate environments, but for public
deployment, a simple user name and password pair is more practical. The following table is a
comparison of the features of authentication types.
Table 124
Comparison of EAP Authentication Types
EAP-MD5 EAP-TLS EAP-TTLS PEAP LEAP
Mutual Authentication No Yes Yes Yes Yes
Certificate – Client No Yes Optional Optional No
Certificate – Server No Yes Yes Yes No
Dynamic Key Exchange No Yes Yes Yes Yes
Credential Integrity None Strong Strong Strong Moderate
Deployment Difficulty Easy Hard Moderate Moderate Moderate
Client Identity Protection No No Yes Yes No