ZyXEL Communications WAP6405 User Manual page 136

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 42 Comparison of EAP Authentication Types
Mutual Authentication
Certificate – Client
Certificate – Server
Dynamic Key Exchange
Credential Integrity
Deployment Difficulty
Client Identity Protection
WPA and WPA2
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 or WPA2 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.
Encryption
WPA improves data encryption by using Temporal Key Integrity Protocol (TKIP), Message Integrity
Check (MIC) and IEEE 802.1x. WPA2 also uses TKIP when required for compatibility reasons, but
offers stronger encryption than TKIP with Advanced Encryption Standard (AES) in the Counter
mode with Cipher block chaining Message authentication code Protocol (CCMP).
TKIP uses 128-bit keys that are dynamically generated and distributed by the authentication server.
AES (Advanced Encryption Standard) is a block cipher that uses a 256-bit mathematical algorithm
called Rijndael. They both include a per-packet key mixing function, a Message Integrity Check
(MIC) named Michael, an extended initialization vector (IV) with sequencing rules, and a re-keying
mechanism.
WPA and WPA2 regularly change and rotate the encryption keys so that the same encryption key is
never used twice.
Appendix D Wireless LANs
EAP-MD5 EAP-TLS
No Yes
No Yes
No Yes
No Yes
None Strong
Easy Hard
No No
WAP6405 User's Guide
136
EAP-TTLS PEAP
Yes Yes
Optional Optional
Yes Yes
Yes Yes
Strong Strong
Moderate Moderate
Yes Yes
LEAP
Yes
No
No
Yes
Moderate
Moderate
No