ZyXEL Communications Prestige 661H Series, User Manual

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Prestige 661H/HW Series User’s Guide
509 Appendix L Wireless LANs
EAP-TLS (Transport Layer Security)
With EAP-TLS, digital certifications are needed by both the server and the wireless stations
for mutual authentication. The server presents a certificate to the client. After validating the
identity of the server, the client sends a different certificate to the server. The exchange of
certificates is done in the open before a secured tunnel is created. This makes user identity
vulnerable to passive attacks. A digital certificate is an electronic ID card that authenticates the
sender’s identity. However, to implement EAP-TLS, you need a Certificate Authority (CA) to
handle certificates, which imposes a management overhead.
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 screen. You may still configure and store keys here, but they will not be used while
Dynamic WEP is enabled.
Note: EAP-MD5 cannot be used with Dynamic WEP Key Exchange