A Privacy Type System for Context-aware Mobile Ambients

Thanks to the advances in technologies, ubiquitous computing (ubicomp) is developing fast with the proliferation of smart devices such as smart phones and tablet computers. However, privacy is an important concern in ubicomp; unless users are confident enough that their privacy is protected, many will be deterred from using such systems. This paper proposes a privacy type system that controls the behaviour of concurrent, context-aware and mobile processes to ensure that private information are not accidentally disclosed. We prove the subject reduction property, which guarantees that a well-typed process is safe and cannot disclose private information to an unauthorised party.