Ensuring Security in It Infrastructures

This paper reviews some of the difficulties that arise in the secureoperating system design. Then a formal framework different fromand more powerful than the existing ones in the literature has beenproposed aiming at supporting multiple security policies in moderncomputing environments. Finally, three novel models in thedifferent areas, namely the confidentiality policy modelDMLR_MLS, the integrity policy model DTE_IPM, and theextended role-based access control model PCM_RBPC forcontrolling process privileges have been introduced, all of whichhave a number of desirable new features.