Motorola AP 5131 - Wireless Access Point, Product Reference Manual, Page: 25 / 698

Introduction 1-9
1.2.8.2 EAP Authentication
The Extensible Authentication Protocol (EAP) feature provides access points and their associated
MU’s an additional measure of security for data transmitted over the wireless network. Using EAP,
authentication between devices is achieved through the exchange and verification of certificates.
EAP is a mutual authentication method whereby both the MU and AP are required to prove their
identities. Like Kerberos, the user loses device authentication if the server cannot provide proof of
device identification.
Using EAP, a user requests connection to a WLAN through the access point. The access point then
requests the identity of the user and transmits that identity to an authentication server. The server
prompts the AP for proof of identity (supplied to the by the user) and then transmits the user data
back to the server to complete the authentication process.
An MU is not able to access the network if not authenticated. When configured for EAP support, the
access point displays the MU as an EAP station.
EAP is only supported on mobile devices running Windows XP, Windows 2000 (using Service Pack #4)
and Windows Mobile 2003. Refer to the system administrator for information on configuring a Radius
Server for EAP (802.1x) support.
For detailed information on EAP configurations, see Configuring 802.1x EAP Authentication on page
6-11 .
1.2.8.3 WEP Encryption
All WLAN devices face possible information theft. Theft occurs when an unauthorized user
eavesdrops to obtain information illegally. The absence of a physical connection makes wireless links
particularly vulnerable to this form of theft. Most forms of WLAN security rely on encryption to
various extents. Encryption entails scrambling and coding information, typically with mathematical
formulas called
algorithms , before the information is transmitted. An algorithm is a set of instructions
or formula for scrambling the data. A key is the specific code used by the algorithm to encrypt or
decrypt the data. Decryption is the decoding and unscrambling of received encrypted data.
The same device, host computer or front-end processor, usually performs both encryption and
decryption. The transmit or receive direction determines whether the encryption or decryption
function is performed. The device takes plain text, encrypts or scrambles the text typically by
mathematically combining the key with the plain text as instructed by the algorithm, then transmits
the data over the network. At the receiving end, another device takes the encrypted text and decrypts,
or unscrambles, the text revealing the original message. An unauthorized user can know the