Deriving implementation-level policies for usage control enforcement

Usage control is concerned with how data is used after access to it has been granted. As such, it is particularly relevant to end users who own the data. System implementations of access and usage control enforcement mechanisms, however, do not always adequately reflect end user requirements. This is due to several reasons, one of which is the problem of mapping concepts in the end user's domain to technical events and artifacts. For instance, semantics of basic operators such as "copy" or "delete", which are fundamental for specifying privacy policies, tend to vary according to context. For this reason they can be mapped to different sets of system events. The behaviour users expect from the system, therefore, may differ from the actual behaviour. In this paper we present a translation of specification-level usage control policies into implementation-level policies which takes into account the precise semantics of domain-specific abstractions. A tool for automating the translation has also been implemented.