Data security in location-aware applications: an approach based on RBAC

Data security in a mobile context is a critical issue. Over the last few years a new category of location-based services, the Enterprise LBS (ELBS), has emerged focusing on the demands of mobility in organisations. These applications pose challenging requirements, including the need of selective access to ELBS based on the position of mobile users and spatially bounded organisational roles. To deal with these requirements a novel access control system, named GEO-RBAC, has been developed. GEO-RBAC extends the NIST RBAC (Role-Based Access Control) standard with the notions of spatial role, role-dependent position, role schema and role instance. Further, roles become enabled/disabled based on the position of the user. In the paper we present GEO-RBAC, a full-fledged RBAC-based model, consisting, like RBAC, of three distinct components: the Core GEO-RBAC, the Hierarchical GEO-RBAC and the Constrained GEO-RBAC. The paper focuses on the innovative aspects that have been introduced in the model to account for the spatial dimension. Further, a rigorous specification of the model (reference model) is presented.

Access control and privacy in location-aware applications

Maria Luisa Damiani

The topic addressed in this thesis concerns the relationship between spatial knowledge and information protection in a mobile setting. The proliferation of mobile devices in an increasingly connected world raises growing concern for information security and privacy. For example, sensitive data recorded in corporate and networked information systems can be accessed from uncontrolled locations, downloaded on mobile terminals and disclosed to unauthorized third parties. The protection of information against improper use and modification in a mobile context poses research questions which solicit the investigation of unconventional protection strategies. In such a perspective, this thesis investigates how to provide strong control over information access based on knowledge of location and movement of individuals. Indeed, the use of spatial information for secure access support has been prospected in mid nineties, yet such a vision has not had a significant follow-up at research level. This work focuses on the definition of a comprehensive framework for the specification and enforcement of spatially-aware access control policies. Policies are spatially-aware in that the access authorization depends on the position of users. The core contribution of this work is the GEO-RBAC model, a role-based access control model that complies with current standards in access control and geo-spatial data representation. In addition, two further models have been specified, which are, to some extent, complementary to GEO-RBAC: the former is a decentralized administration model for the specification of GEO-RBAC access control policies in large organizations; the latter is a location privacy model which can be integrated into the GEO-RBAC framework to protect personal location information, for example in Location Based Services applications. The thesis addresses also issues related to the design of a system based on GEO-RBAC: an architecture has been defined based on which a prototype has been then developed. The use of geographical knowledge in security is a novel area of research and that motivates the existence of several open issues. Some of these have been discussed in the dissertation and a possible direction of research has been finally prospected for future activity.

EPFL2008

GEO-RBAC: A spatially aware RBAC

Maria Luisa Damiani

Securing access to data in location- based services and mobile applications requires the definition of spatially aware access- control systems. Even if some approaches have already been proposed either in the context of geographic database systems or context- aware applications, a comprehensive framework, general and flexible enough to deal with spatial aspects in real mobile applications, is still missing. In this paper, we make one step toward this direction and present GEO- RBAC, an extension of the RBAC model enhanced with spatial- and location- based information. In GEOR-BAC, spatial entities are used to model objects, user positions, and geographically bounded roles. Roles are activated based on the position of the user. Besides a physical position, obtained from a given mobile terminal or a cellular phone, users are also assigned a logical and device- independent position, representing the feature ( the road, the town, the region) in which they are located. To enhance flexibility and reusability, we also introduce the concept of role schema, specifying the name of the role, as well as the type of the role spatial boundary and the granularity of the logical position. We then extend GEO- RBAC to support hierarchies, modeling permission, user, and activation inheritance, and separation of duty constraints. The proposed classes of constraints extend the conventional ones to deal with different granularities ( schema/ instance level) and spatial information. We conclude the paper with an analysis of several properties concerning the resulting model.

2007

Access control and privacy in location-aware applications

Maria Luisa Damiani

EPFL2008