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Configuring wpa/wpa2 using tkip and – Motorola Series Switch WS5100 User Manual

Page 117

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Network Setup

4-43

Configuring WPA/WPA2 using TKIP and CCMP

Wi-Fi Protected Access (WPA) is a robust encryption scheme specified in the IEEE Wireless Fidelity (Wi-Fi)
standard, 802.11i. WPA provides more sophisticated data encryption than WEP. WPA is designed for
corporate networks and small-business environments where more wireless traffic allows quicker discovery
of encryption keys by an unauthorized person.

WPA's encryption method is Temporal Key Integrity Protocol (TKIP). TKIP addresses WEP’s weaknesses with
a re-keying mechanism, a per-packet mixing function, a message integrity check, and an extended
initialization vector. WPA also provides strong user authentication based on 802.1x EAP.

WPA2 is a newer 802.11i standard that provides even stronger wireless security than WPA and WEP. CCMP
is the security standard used by the Advanced Encryption Standard (AES). AES serves the same function TKIP
does for WPA-TKIP. CCMP computes a Message Integrity Check (MIC) using the proven Cipher Block Chaining
(CBC) technique. Changing just one bit in a message produces a totally different result.

WPA2-CCMP is based on the concept of a Robust Security Network (RSN), which defines a hierarchy of keys
with a limited lifetime (similar to TKIP). Like TKIP, the keys the administrator provides are used to derive other
keys. Messages are encrypted using a 128-bit secret key and a 128-bit block of data. The end result is an
encryption scheme as secure as any the switch provides.

To configure WPA/WPA2-TKIP/CCMP encryption:

1. Select

Network

>

Wireless LANs

from the main menu tree.

2. Select an existing WLAN from those displayed within the

Configuration

tab and click the

Edit

button.

A WLAN screen displays with the WLAN’s existing configuration. Refer to the

Authentication

and

Encryption

columns to assess the WLAN’s existing security configuration.

3. Select either the

WPA/WPA2-TKIP

or

WPA2-CCMP

button from within the

Encryption field.

4. Click the

Config

button to the right of the WPA/WPA2-TKIP and WPA2-CCMP checkboxes.

The

WPA/WPA2-TKIP/CCMP

screen displays. This single screen can be used to configure either WPA/

WPA2-TKIP or WPA-CCMP.