Mobile Encounter-based Social Sybil Control

We present a novel “Proof of Social Contact” approach to Sybil control that utilizes the analysis of digitally signed information about digitally signed pairwise encounters between mobile devices that are logged in a distributed ledger. To illustrate the approach, we show examples of analysis using binary classification techniques under two different adversary detection models, and evaluate them using a real-world mobile device encounter trace. We discuss a number of open problems and future directions that could be pursued by researchers in the field to realize and improve such a system and build on top of it.