TRBACN: A temporal authorization model

Abstract

We show how the family of temporal role-based access control (TRBAC) models from [6], the TRBAC° models, may be equivalently represented in a considerably simpler and more efficiently implemented way. We call the latter the TRBACN models. To specify TRBACn models, stratified normal clause logic is sufficient. To compute with TRBACN models, any procedural semantics that enables the perfect model of a stratified theory to be generated may be used. Although TRBACN security models have a much simpler representation than TRBACO models, we show that TRBACN and TRBACO models are equivalent in terms of their expressive power.