ZyXEL Communications G-470 User Manual

Page of 110
G-470 User’s Guide
90
Appendix B
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
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 24   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