Wi-Fi Protected Access. An improved security standard for wireless networks that provides strong data protection and network access control. WPA was developed by the Wi-Fi Alliance and addresses all known WEP vulnerabilities. It provides strong data protection by using encryption, as well as strong access controls and 802.1X-based user authentication which was largely missing in WEP. WPA is designed to secure all versions of 802.11 devices, including 802.11b, 802.11a, and 802.11g, dual-band and tri-mode. WPA can be enabled in two versions, WPA-Personal and WPA-Enterprise. WPA-Personal protects against unauthorized network access by utilizing a set-up pass phrase, or pre-shared key. WPA-Enterprise verifies network users through an authentication server. In either mode, WPA utilizes 128-bit encryption keys and dynamic session keys to ensure the wireless network's privacy and security. (See PSK, WEP, WPA2).