Abstract: As an expansion of LAN, the WLAN reduces the cost of building a network infrastructure and enables the users to enjoy the mobile services.The 802.11 standard includes a wired equivalent privacy (WEP) protocol, which is used to protect communications from eaves dropping.Several serious security flaws in this protocol have been discovered.To cope with this problem, IEEE802.11i Group proposed adapting TKIP protocol to enhance the WLAN security.In this paper, through analyzing TKIP protocol, concrete security analyses of TKIP protocol are made.It was shown that although TKIP did indeed increase security and result in significant, provable security gains, but it still failed to meet the need of users in a WLAN environment.

Key words: security analysis, WEP, TKIP, WLAN