NETGEAR MR814 - 802.11b Cable/DSL Wireless Router, Reference Manual

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Reference Manual for the MR814 v3 Cable/DSL Wireless Router
Wireless Networking Basics D-9
202-10039-01
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 will have to support
WPA. NETGEAR will implement WPA on client and access point products and make this
available in the second half of 2003. Existing Wi-Fi certified products will have one year to add
WPA support or they will loose their Wi-Fi certification.
The 802.11i standard is currently in draft form, with ratification due at the end of 2003. While the
new IEEE 802.11i standard is being ratified, wireless vendors have agreed on WPA as an
interoperable interim standard.
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 don't 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.