Reasoning about obfuscated private information: who have lied and how to lie

Abstract

In ubiquitous environments, context sharing among agents should be made privacy-conscious. Privacy preferences are generally specified to govern the context exchanging among agents. Besides who has rights to see what information, a user's privacy preference could also designate who has rights to have what obfuscated information. By obfuscation, people could present their private information in a coarser granularity, or simply in a falsified manner, depending on the specific situations. Nevertheless, people cannot randomly obfuscate their private information because by reasoning the recipients could detect the obfuscation. In this paper, we present a Bayesian network-based method to reason about the obfuscation. On the one hand, it can be used to find if the received information has been obfuscated, and if so, what the true information could be; on the other hand, it can be used to help the obfuscators reasonably obfuscate their private information.