Date of Award

Fall 8-2020

Document Type


Degree Name

Doctor of Philosophy (PhD)


Cyberspace Engineering

First Advisor

Jean Gourd


Smart devices (mobile devices, laptops, tablets, etc.) can receive signals from different radio frequency devices that are within range. As these devices move between networks (e.g., Wi-Fi hotspots, cellphone towers, etc.), they receive broadcast messages from access points, some of which can be used to collect useful information. This information can be utilized in a variety of ways, such as to establish a connection, to share information, to locate devices, and to identify users, which is central to this dissertation. The principal benefit of a broadcast message is that smart devices can read and process the embedded information without first being connected to the corresponding network. Moreover, broadcast messages can be received only within the range of the wireless access point that sends the broadcast, thus inherently limiting access to only those devices in close physical proximity, which may facilitate many applications that are dependent on proximity. In our research, we utilize data contained in these broadcast messages to implement a two-factor authentication (2FA) system that, unlike existing methods, does not require any extra effort on the part of the users of the system. By determining if two devices are in the same physical location and sufficiently close to each other, we can ensure that they belong to the same user. This system depends on something that a user knows, something that a user owns, and—a significant contribution of this work—something that is in the user’s environment.