Reference Manual for the NETGEAR ProSafe Wireless Access Point 802.11g WG302
B-16
Wireless Networking Basics
July 2005 v3.0
Is WPA/WPA2 Perfect?
WPA/WPA2 is not without its vulnerabilities. Specifically, it is susceptible to denial of service
(DoS) attacks. If the access point receives two data packets that fail the message integrity code
(MIC) within 60 seconds of each other, then the network is under an active attack, and as a result,
the access point employs counter measures, which include disassociating each station using the
access point. This prevents an attacker from gleaning information about the encryption key and
alerts administrators, but it also causes users to lose network connectivity for 60 seconds. More
than anything else, this may just prove that no single security tactic is completely invulnerable.
WPA/WPA2 is a definite step forward in WLAN security over WEP and has to be thought of as a
single part of an end-to-end network security strategy.
Product Support for WPA/WPA2
Starting in August, 2003, NETGEAR, Inc. wireless Wi-Fi certified products will support the WPA
standard. NETGEAR, Inc. wireless products that had their Wi-Fi certification approved before
August, 2003 will have one year to add WPA so as to maintain their Wi-Fi certification.
WPA/WPA2 requires software changes to the following:
•
Wireless access points
•
Wireless network adapters
•
Wireless client programs
Supporting a Mixture of WPA, WPA2, and WEP Wireless Clients is Discouraged
To support the gradual transition of WEP-based wireless networks to WPA/WPA2, a wireless AP
can support both WEP and WPA/WPA2 clients at the same time. During the association, the
wireless AP determines which clients use WEP and which clients use WPA/WPA2. The
disadvantage to supporting a mixture of WEP and WPA/WPA2 clients is that the global encryption
key is not dynamic. This is because WEP-based clients cannot support it. All other benefits to the
WPA clients, such as integrity, are maintained.
However, a mixed mode supporting WPA/WPA2 and non-WPA/WPA2 clients would offer
network security that is no better than that obtained with a non-WPA/WPA2 network, and thus this
mode of operation is discouraged.
