Security Considerations for a Distributed LocationService

Abstract

Mobile computing, wireless communications, and cheap location tracking and navigation systems have made location data a valuable and available commodity for many different kinds of computing applications. However, there are fears that this new wealth of personal location information will lead to new security risks, to the invasion of the privacy of people and organizations. In this paper, we discuss security requirements faced by a location service in different organizational contexts. We argue that fine-grained access control requires a symbolic location model over which access control is specified. We outline the salient features of a location service supporting such a location model. The two main classical security models, Lampson's access matrix and Bell-LaPadula's security labels, are analyzed with view to their application to location information. We argue that those schemes need to be generalized to deal with multiple targets in order to be applicable to location information. Based on the generalized models, we propose a concrete security model for location information which protects both personal and organizational privacy. We have implemented this model over a prototype implementation of a general location service.