User’s Guide for the WG602 v3 54 Mbps Wireless Access Point
B-10
Wireless Networking Basics
202-10060-01, September 2004
How Does WPA Compare to IEEE 802.11i?
WPA will be forward compatible with the IEEE 802.11i security specification currently under
development. WPA is a subset of the current 802.11i draft and uses certain pieces of the 802.11i
draft that are ready to bring to market today, such as 802.1x and TKIP. The main pieces of the
802.11i draft that are not included in WPA are secure IBSS (Ad-Hoc mode), secure fast handoff
(for specialized 802.11 VoIP phones), as well as enhanced encryption protocols such as
AES-CCMP. These features are either not yet ready for market or will require hardware upgrades
to implement.
What are the Key Features of WPA Security?
The following security features are included in the WPA standard:
•
WPA Authentication
•
WPA Encryption Key Management
–
Temporal Key Integrity Protocol (TKIP)
–
Michael
message integrity code
(MIC)
–
AES Support
•
Support for a Mixture of WPA and WEP Wireless Clients
These features are discussed below.
WPA addresses most of the known WEP vulnerabilities and is primarily intended for wireless
infrastructure networks as found in the enterprise. This infrastructure includes stations, access
points, and authentication servers (typically RADIUS servers). The RADIUS server holds (or has
access to) user credentials (e.g., user names and passwords) and authenticates wireless users
before they gain access to the network.
The strength WPA comes from an integrated sequence of operations that encompass 802.1X/EAP
authentication and sophisticated key management and encryption techniques. Its major operations
include:
•
Network security capability determination. This occurs at the 802.11 level and is
communicated through WPA information elements in Beacon, Probe Response, and (Re)
Association Requests. Information in these elements includes the authentication method
(802.1X or Pre-shared key) and the preferred cipher suite (WEP, TKIP, or AES).