SoK: Differential Privacies
Abstract
Shortly after it was first introduced in 2006, differential privacy
became the flagship data privacy definition. Since then, numerous variants and
extensions were proposed to adapt it to different scenarios and attacker models.
In this work, we propose a systematic taxonomy of these variants and extensions.
We list all data privacy definitions based on differential privacy, and
partition them into seven categories, depending on which aspect of the original
definition is modified.
These categories act like dimensions: variants from the same category cannot
be combined, but variants from different categories can be combined to form new
definitions. We also establish a partial ordering of relative strength between
these notions by summarizing existing results. Furthermore, we list which of
these definitions satisfy some desirable properties, like composition,
post-processing, and convexity by either providing a novel proof or collecting
existing ones.