Requirements for a location-based access control model

Location-based access control (LBAC) takes a mobile user's current position into account when making the decision if he should be allowed to access a particular resource like a file or service. For example using LBAC we can enforce that a nurse is only allowed to view a patient's data using a PDA when she stays at the premises of the hospital. There are a couple of research papers that propose data models for LBAC; almost all of them are extensions of Role-based Access Control (RBAC). In the paper at hand we first motivate the employment of LBAC by some application scenarios before we review the most important LBAC-models. Despite the body of research in the field of LBAC we could identify requirements that cannot be covered with the available models; these requirements are discussed in detail.