Beacon-Stuffing: Wi-Fi without Associations

The design of Wi-Fi networks mimics the behavior of wired networks. For example, a Wi-Fi network interface can send and receive packets only after associating to a Wi-Fi access point (AP). In this paper, we show that the concept of association limits the capabilities of wireless networks. We present a scheme, called beacon-stuffing, that allows Wi-Fi clients to communicate without associating to any network. Beacon-stuffing enables several new applications over Wi-Fi networks, and we describe three of them in this paper: improved AP selection, delivering location-specific advertisements, and providing coupons over Wi-Fi networks without requiring the Wi-Fi client to associate to any AP.