User Manual

Chapter 13: Configuring Security
WPA/WPA2 Enterprise (RADIUS)
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Psion Teklogix 9160 Wireless Gateway User Manual
Cipher Suites Select the cipher you want to use from the drop-down menu:
• TKIP
• CCMP (AES)
•Both
Temporal Key Integrity Protocol ( TKIP ) is the default.
TKIP provides a more secure encryption solution than WEP keys. The TKIP process more frequently
changes the encryption key used and better ensures that the same key will not be re-used to encrypt
data (a weakness of WEP).
TKIP uses a 128-bit “temporal key” shared by clients and access points. The temporal key is com-
bined with the client's MAC address and a 16-octet initialization vector to produce the key that will
encrypt the data. This ensures that each client station uses a different key to encrypt data.
TKIP uses RC4 to perform the encryption, which is the same as WEP. But TKIP changes temporal
keys every 10,000 packets and distributes them, thereby greatly improving the security of the network.
Counter mode/CBC-MAC Protocol ( CCMP ) is an encryption method for IEEE 802.11i that uses
the
Advanced Encryption Algorithm ( AES ). It uses a CCM combined with Cipher Block Chaining
Counter mode (CBC-CTR) and Cipher Block Chaining Message Authentication Code (CBC-MAC)
for encryption and message integrity.
When the authentication algorithm is set to “
Both ”, both TKIP and AES clients can associate with the
access point. Client stations configured to use WPA with RADIUS must have one of the following to
be able to associate with the AP:
• A valid TKIP RADIUS IP address and valid shared Key.
• A valid CCMP (AES) IP address and valid shared Key.
Clients not configured to use WPA with RADIUS will not be able to associate with AP.
Both is the default. When the authentication algorithm is set to “Both”, client stations configured to
use WPA with RADIUS must have one of the following:
• A valid TKIP RADIUS IP address and RADIUS Key.
• A valid CCMP (AES) IP address and RADIUS Key.
Field Description
Table 13.12 WPA/WPA2 Enterprise (RADIUS) Security Settings