Reference Manual for the NETGEAR ProSafe Wireless Access Point 802.11g WG302
Wireless Networking Basics
B-9
July 2005 v3.0
WPA and WPA2 offer the following benefits:
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Enhanced data privacy
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Robust key management
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Data origin authentication
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Data integrity protection
The Wi-Fi Alliance is now performing interoperability certification testing on Wi-Fi Protected
Access products. Starting August of 2003, all new Wi-Fi certified products have to support WPA.
NETGEAR is implementing WPA and WPA2 on client and access point products. The 802.11i
standard was ratified in 2004.
How Does WPA Compare to WEP?
WEP is a data encryption method and is not intended as a user authentication mechanism. WPA
user authentication is implemented using 802.1x and the Extensible Authentication Protocol
(EAP). Support for 802.1x authentication is required in WPA. In the 802.11 standard, 802.1x
authentication was optional. For details on EAP specifically, refer to IETF's RFC 2284.
With 802.11 WEP, all access points and client wireless adapters on a particular wireless LAN must
use the same encryption key. A major problem with the 802.11 standard is that the keys are
cumbersome to change. If you do not update the WEP keys often, an unauthorized person with a
sniffing tool can monitor your network for less than a day and decode the encrypted messages.
Products based on the 802.11 standard alone offer system administrators no effective method to
update the keys.
For 802.11, WEP encryption is optional. For WPA, encryption using Temporal Key Integrity
Protocol (TKIP) is required. TKIP replaces WEP with a new encryption algorithm that is stronger
than the WEP algorithm, but that uses the calculation facilities present on existing wireless devices
to perform encryption operations. TKIP provides important data encryption enhancements
including 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. Through
these enhancements, TKIP addresses all of known WEP vulnerabilities.