Event Systems and Access Control
  We consider the interpretations of notions of access control (permissions, interdictions, obligations, and user rights) as run-time properties of information systems specified as event systems with fairness. We give proof rules for verifying that an access control policy is enforced in a system, and consider preservation of access control by refinement of event systems. In particular, refinement of user rights is non-trivial; we propose to combine low-level user rights and system obligations to implement high-level user rights. 
Dominique M\'ery (INRIA Lorraine - LORIA), Stephan Merz (INRIA   Lorraine - LORIA)