Link-Layer Protection in 802.11i WLANs with Dummy Authentication

摘要

The current 802.11i standard can provide data confidentiality, integrity and mutual authentication in enterprise Wireless Local Area Networks (WLANs). However, secure communication can only be provided after successful authentication and a robust security network association is established. In general, the wireless link layer is not protected by the current standard in WLANs, which leads to many possible attacks, especially in public open-access wireless networks. We argue that regardless of the type of network under consideration, link-layer protection and data confidentiality are of great importance in wireless applications. In this paper, we first identify and analyze the security issues ignored by the current 802.11 security standard. Then we propose our solution to patch the current 802.11i standard and address all those issues with a new dummy authentication key-establishment algorithm. Dummy means no real authentication for a user. In dummy authentication, we apply public-key cryptography's key-establishment technique to the 802.11 MAC protocol. Our solution can provide link-layer data encryption in open-access wireless networks, separate session encryption keys for different users, and protection for important frames such as management and null data frames as well as Extensible Authentication Protocol (EAP) messages.