3com WX1200 3CRWX120695A User Manual

C

HAPTER

 13: C

ONFIGURING

 U

SER

 E

NCRYPTION

Wi-Fi Protected Access (WPA) is a security enhancement to the IEEE 
802.11 wireless standard. WPA provides enhanced encryption with new 
cipher suites and provides per-packet message integrity checks. WPA is 
based on the 802.11i standard. You can use WPA with 802.1X 
authentication. If the client does not support 802.1X, you can use a 
preshared key on the MAP and the client for authentication.

WPA supports the following cipher suites for packet encryption, listed 
from most secure to least secure:

„

Counter Mode with Cipher Block Chaining Message 
Authentication Code Protocol (CCMP) — CCMP provides 
Advanced Encryption Standard (AES) data encryption. To provide 
message integrity, CCMP uses the Cipher Block Chaining Message 
Authentication Code (CBC-MAC). 

„

Temporal Key Integrity Protocol (TKIP) — TKIP uses the RC4 
encryption algorithm, a 128-bit encryption key, a 48-bit initialization 
vector (IV), and a message integrity code (MIC) called Michael. 

„

Wired Equivalent Privacy (WEP) with 104-bit keys — 104-bit WEP 
uses the RC4 encryption algorithm with a 104-bit key.

„

WEP with 40-bit keys — 40-bit WEP uses the RC4 encryption 
algorithm with a 40-bit key. 

You can configure MAPs to support one or more of these cipher suites. 
For all of these cipher suites, MSS dynamically generates unique session 
keys for each session. MSS periodically changes the keys to reduce the 
likelihood that a network intruder can intercept enough frames to 
decode a key.