Start Date: 2015-03-05 End Date: 2018-03-05
Access control is a central issue in building secure computer systems. It is defined as the ability to permit or deny access to a particular resource by a
particular entity. Access control must prevent unauthorized disclosure of information and improper modification of resources, while provide access to
authorized entities. Usage control is a modern approach to access control in open, heterogeneous network-connected computer environments. The goal of
the project was to propose a formalism, which would be able to provide an adequate formalization of the main models of usage control and would be
suitable for their analysis and verification. For this purpose, we chose a rewriting-based formalism, the ρLog calculus, compared it to other theories of
rewriting, and showed connections between the control requirements and main properties of rewrite systems. Furthermore, one of such important
properties, confluence, has been studied in detail for a variant of pattern calculus, which generalizes interesting rewriting-based formalisms.