BibTeX for papers by David Kotz; for complete/updated list see https://www.cs.dartmouth.edu/~kotz/research/papers.html @InProceedings{pierson:snap, author = {Timothy J. Pierson and Travis Peters and Ronald Peterson and David Kotz}, title = {Proximity Detection with Single-Antenna IoT Devices}, booktitle = {Proceedings of the ACM International Conference on Mobile Computing and Networking (MobiCom)}, year = 2019, month = {October}, articleno = 21, numpages = 15, publisher = {ACM}, copyright = {ACM}, DOI = {10.1145/3300061.3300120}, URL = {https://www.cs.dartmouth.edu/~kotz/research/pierson-snap/index.html}, abstract = {Providing secure communications between wireless devices that encounter each other on an ad-hoc basis is a challenge that has not yet been fully addressed. In these cases, close physical proximity among devices that have never shared a secret key is sometimes used as a basis of trust; devices in close proximity are deemed trustworthy while more distant devices are viewed as potential adversaries. Because radio waves are invisible, however, a user may believe a wireless device is communicating with a nearby device when in fact the user's device is communicating with a distant adversary. Researchers have previously proposed methods for multi-antenna devices to ascertain physical proximity with other devices, but devices with a single antenna, such as those commonly used in the Internet of Things, cannot take advantage of these techniques. \par We present theoretical and practical evaluation of a method called SNAP -- SiNgle Antenna Proximity -- that allows a single-antenna Wi-Fi device to quickly determine proximity with another Wi-Fi device. Our proximity detection technique leverages the repeating nature Wi-Fi's preamble and the behavior of a signal in a transmitting antenna's near-field region to detect proximity with high probability; SNAP never falsely declares proximity at ranges longer than 14 cm.}, }