Study And Implementation Of WLAN Security Technology Based On IEEE 802.11i

In this new era, Wireless LAN is one of the most promising technologies in the field of telecommunication. WLAN is changing our traditional ways of working and studying, and make it available to achieve high quality services of voice, data and image in any time at any place. However, with the constant popularization of WLAN, the security of WLAN has been becoming a hot topic in the research of present computer networks. If security problems are not solved properly, they will restrict the further development of WLAN.At first, this paper reviews WLAN standards and analyzes security threats and security risks in WLAN. Then severe flaws of security mechanisms based on WEP specified in IEEE 802.11 are addressed. It is also developed about authentication and access control, data privacy protocols and dynamic key management in IEEE 802.11i. Finally, according to IEEE 802.1X, EAP-TLS authentication method and RADIUS protocol, we designed and implemented a WLAN security system on Linux platform. It combines with Open Source Code Project including OpenSSL, Host AP, Open1x and FreeRADIUS, and can meet the demand of RSNA framework defined in IEEE 802.11i. We selected a WLAN attack tool, WinAircrackPack, which is readily available on the Internet, and tried to crack the keys used in traditional WLAN system and the system we implemented respectively. The results express the former can be cracked successfuly and the latter can not. It also proves that our system can defend against the known key attacks effectively.