Ontology-based privacy protection for smartphone: A firewall implementation

Overview & Synopsis

During the past few years, smartphones have tended to replace feature phones in the user's pocket. They allow users to access various applications and services that aim at making their life easier. For that purpose, some applications access private data such as the user's location and do not always ask for the user's consent. Data collection is a growing issue for the user's privacy and the current protection mechanisms have proved to be inefficient [1]. In a previous work [2], we have proposed a real-time firewall that aims at preventing malicious applications from accessing private data on an Android smartphone. The firewall relies on an ontology that represents privacy protection concepts and the digital identity of a smartphone's user. Our firewall is based on a set of privacy rules and applies description logic reasoning to decide whether access to private data by a given application may be authorized or not. However, the use of semantic technologies can be an issue when implemented on devices that offer low computation capabilities. The contribution of the present work is an optimized implementation of the firewall that offers good performances as well as good privacy protection. This paper is organized as follows: the first part is a description of our optimized implementation; the second one details the criteria we have chosen to evaluate the implementation and is followed by the results of our tests on this implementation. Finally, the conclusion of the paper highlights the interest of the approach and proposes future improvements.