sed access. Key management Creation, protection and distribution of keys used for encrypting data and other messages. Message integrity Checks that a message has not been modified during transmission. Wireless LAN Security authentication and weak encryption. The interim development and deployment of enhancements to 802.11 security has been led by the Wi-Fi Alliance with the release of WPA and WPA2. The shortcomings of the original 802.11 standard were addressed with the ratification in 2004 of the 802.11i standard, which provides a standards basis for WPA and WPA2. The progressive enhancements to WLAN security, and the technologies underlying these enhancements, are described in the Sections "WEP - Wired Equivalent Privacy Encryption, p. 209", "Wi-Fi Protected Access; WPA, p. 212" and "IEEE 802.11i and WPA2, p. 219", and the Sections "WLAN Security Measures, p. 230" and "Wireless Hotspot Security, p. 236" then return to the practical aspects of ensuring security in wireless LANs, at wireless hotspots and some specific aspects of VoWLAN security. WEP - Wired Equivalent Privacy Encryption As the name suggests, the intention of WEP was to provide a level of security equivalent to a wired network, although this aspiration was not achieved because of a fundamental cryptographic weakness. From the list of security measures summarised in Table 8-1, WEP provides a limited degree of access control and data privacy using a secret key, typically a passphrase, that is entered into the access point and is required to be known by any station attempting to associate with the access point. Without knowledge of the passphrase, a station will be able to see network traffic but will not be able to associate or easily decrypt data. WEP encryption translates the passphrase into a 40-bit secret key, to which a 24-bit initialisation vector (IV; see Glossary) is added to create a 64-bit encryption key. As an interim attempt to strengthen WEP encryption, some vendors enhanced the key length to 128-bit (104-bit + 24-bit IV). This proved t