ZyXEL Communications Unified Security Gateway ZyWALL 300, User Manual

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Appendix E Wireless LANs
ZyWALL USG 300 User’s Guide
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authentication method does not support data encryption with dynamic session
key. You must configure WEP encryption keys for data encryption.
EAP-TLS (Transport Layer Security)
With EAP-TLS, digital certifications are needed by both the server and the wireless
clients 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 security configuration screen. You may still configure and store
keys, but they will not be used while dynamic WEP is enabled.