Algorithmic advances in anonymous communication over networks

Over the years, researchers have thought extensively about how to communicate anonymously over a network. In this position paper, we first provide an overview of the current research landscape-including a discussion of common communication and anonymity models-and examples of prominent work in this space. In the second half of the paper, we present our thoughts on future directions of interest in this area. In short, we notice an increasing amount of work in the anonymity literature that tackles nearly omnipotent adversaries, which presumably represent the NSA or a similarly powerful surveillance agency. Such strong adversarial models can only be defeated through heavy-handed techniques that may be difficult to scale in practice. We therefore present two guidelines that have guided our own algorithmic problem formulation in this space. These guidelines suggest alternative research directions that (1) exploit surveillance agencies' weaknesses at the physical layer, and (2) consider the many weaker, but still relevant, adversaries who contribute to global censorship and surveillance.