Website Fingerprinting on LEO Satellite Internet

Abstract

Although encrypted channels, like those provided by anonymity networks such as Tor, have been put into effect, network adversaries have proven their capability to undermine users' browsing privacy through website fingerprinting attacks.

This study examines the susceptibility of Tor users to website fingerprinting when data is transmitted via Low Earth Orbit (LEO) satellite Internet connections. To this end, we design an experimental testbed that includes a Starlink satellite Internet connection and a traditional fiber connection. We use this testbed to gather Tor browsing data over both LEO and fiber connections, enabling a study over the effectiveness of website fingerprinting attacks in these different settings. Besides using our testbed to gather Tor traces, we also collect simple website accesses via Firefox in order to characterize Tor and non-Tor traffic in both Starlink and fiber network settings.

We were able to observe clear differences between Starlink and fiber connections for both Tor and non-Tor traffic when analyzing metrics such as average page load time, average number of packets, and average length of packets. Ultimately, our research leveraging state-of-the-art website fingerprinting attacks suggests that Tor traffic transmitted through Starlink is just as susceptible to these attacks as traffic over fiber links, despite the unique networking characteristics of Starlink connections. However, we find out that the deployment of website fingerprinting defences can substantially decrease the effectiveness of these attacks on Tor traffic exchanged via Starlink, resulting only in a slight bandwidth usage overhead when compared to the deployment of the same defenses in fiber connections.