Contextual Privacy Management in Extended Role Based Access Control Model

Abstract

Typically, informational privacy aims to protect personal data from unauthorized access. In this paper, we propose to use the OrBAC model enhanced by some concepts to model privacy policies. We will take into account the concepts of consent, accuracy, purposes of the access and provisional obligation within role-based access control model.

First, we focus on modelling of the requirement of the data owner consent before delivering the sensitive data. The subscriber defines that he must be notified before terminating the access. The access is delayed until the satisfaction of this condition.

On the other hand, the accuracy of the sensitive data is usually underestimated within privacy models. We design an object hierarchy based on predefined accuracy levels. For this, we propose a derivation rule of sensitive objects. So, data owner can define authorisations based on different object accuracies.

Furthermore, access control models usually permit the access to the stored data based on the role of the requester. We propose to extend this concept to take into account the purpose of the access. For this, we take advantage of the OrBAC user-declared context.

Finally, we propose in this work to model the provisional obligations after accessing personal information. Third parties must notify data controller about further usage over collected data.

To validate our approach, we show how the resulting model can be used to model the privacy policy for a location-based service. This can be applied within a mobile operator organization.