Type Checking Privacy Policies in the π-calculus

Abstract

Abstract. In this paper we propose a formal framework for studying privacy. Our framework is based on the π-calculus with groups accompanied by a type system for capturing privacy requirements relating to information collection, information processing and information dissemination. The framework incorporates a privacy policy language. We show that a system respects a privacy policy if the typing of the system is compatible with the policy. We illustrate our methodology via analysis of privacy-aware schemes proposed for electronic traffic pricing.

Privacy by typing in the $\pi$-calculus

“…To conclude, we mention our previous work of [32,33,29]. In these works we again employed the π-calculus with groups [10] accompanied by a type system for capturing privacy-related notions.…”

“…The type system of [32] was based on i/o and linear types for reasoning about information processing and dissemination and a two-level type structure for distinguishing between the permissions associated with a name upon receipt and upon delivery by a process. In [33], the type system was reconstructed and simplified: the notion of groups was employed to distinguish between the different entities of a system and we employ the type system in order to type-check a system against the standard types of the π-calculus with groups while performing type inference to associate permissions with the different components of a system. Furthermore, a safety criterion was proved for the framework thus providing the necessary machinery for proving privacy preservation by typing.…”

“…Furthermore, a safety criterion was proved for the framework thus providing the necessary machinery for proving privacy preservation by typing. Finally, in [29] we extended the results of [33] to encompass the notion of a purpose. In the present paper, we extend these works providing a more thorough treatment of privacy violations, including data identification, aggregation and secondary use.…”