PlexC: a policy language for exposure control

Abstract

With the widespread use of online social networks and mobile devices, it is not uncommon for people to continuously broadcast contextual information such as their current location or activity. These technologies present both new opportunities for social engagement and new risks to privacy, and traditional static "write once" disclosure policies are not well suited for controlling aggregate exposure risks in the current technological landscape. Therefore, we present PlexC, a new policy language designed for exposure control. We take advantage of several recent user studies to identify a set of language requirements and features, providing the expressive power to accommodate information sharing in dynamic environments. In our evaluation we show that PlexC can concisely express common policy idioms drawn from survey responses, in addition to more complex information sharing scenarios.