You could drive a truck through the holes in the 802.11 WEP (Wired Equivalent Privacy) protocol. But emerging wireless security technologies--IEEE's 802.11i and the Wi-Fi Alliance's WPA (Wi-Fi Protected Access)--are designed to avoid those holes.
802.11i overhauls the IEEE's 802.11 security standard. The more airtight 802.11i specifications are in the final stages of the standards process, with compliant products due to market this year. But 802.11i, which includes data integrity and encryption, is complex and may not interoperate with your existing wireless hardware.
If you have a large base of older 802.11b clients and APs (access points), tearing them out isn't realistic. Instead, WPA may be a better fit for now. WPA is a subset of the 802.11i standard that provides security for large enterprises and small office/home office WLANs. It was designed to work with 802.11i, so it'll give you a head start on a future 802.11i deployment. WPA equipment is available now from Airespace, Aruba, Buffalo Technology, Cisco Systems, Proxim and other vendors.
News source: Network Computing