Hiding Signal Strength Interference from Outside Adversaries

TL;DR

This paper introduces a formal framework to analyze how adjusting transmitted signal strength can prevent outside adversaries from detecting people's presence via Wi-Fi signal analysis.

Contribution

It provides a formal framework and identifies scenarios and protocols that can effectively prevent passive signal strength inference.

Findings

Formal framework for signal strength privacy analysis

Protocols that limit passive detection of presence

Identification of scenarios where privacy can be enhanced

Abstract

The presence of people can be detected by passively observing the signal strength of Wifi and related forms of communication. This paper tackles the question of how and when can this be prevented by adjustments to the transmitted signal strength, and other similar measures. The main contribution of this paper is a formal framework to analyze this problem, and the identification of several scenarios and corresponding protocols which can prevent or limit the inference from passive signal strength snooping.