Browsing by Subject "Opacity"

Now showing items 1-19 of 19

    • Article  

      Coverage analysis of mobile agent trajectory via state-based opacity formulations 

      Saboori, A.; Hadjicostis, Christoforos N. (2011)
      This paper performs coverage analysis of mobile agent trajectory utilizing discrete event system models and employing state-based notions of opacity. Non-deterministic finite automata with partial observation on their ...
    • Article  

      Current-state opacity formulations in probabilistic finite automata 

      Saboori, A.; Hadjicostis, Christoforos N. (2014)
      A system is said to be current-state opaque if the entrance of the system state to a set of secret states remains opaque (uncertain) to an intruder - at least until the system leaves the set of secret states. This notion ...
    • Conference Object  

      Initial state opacity in stochastic des 

      Keroglou, C.; Hadjicostis, Christoforos N. (2013)
      A non-deterministic finite automaton is initial-state opaque if the membership of its true initial state to a given set of secret states S remains opaque (i.e., uncertain) to an intruder who observes system activity through ...
    • Conference Object  

      New image processing models for opacity image analysis in chest radiographs 

      Pattichis, Marios S.; Muralldharan, H.; Pattichis, Constantinos S.; Soliz, P. (Institute of Electrical and Electronics Engineers Inc., 2002)
      The aim of this research is to develop new image processing models that can be used to characterize single opacities and opacity density within pre-selected regions of interest (ROI). We derive our new image processing ...
    • Conference Object  

      Notions of security and opacity in discrete event systems 

      Saboori, A.; Hadjicostis, Christoforos N. (2007)
      In this paper, we follow a state-based approach to extend the notion of opacity in computer security to discrete event systems. A system is (S, P)-opaque if the evolution of its true state through a set of secret states S ...
    • Article  

      On the history of diagnosability and opacity in discrete event systems 

      Lafortune, S.; Lin, F.; Hadjicostis, Christoforos N. (2018)
      This paper presents historical remarks on key projects and papers that led to the development of a theory of event diagnosis for discrete event systems modeled by finite-state automata or Petri nets in the 1990s. The goal ...
    • Conference Object  

      Opacity formulations and verification in discrete event systems 

      Hadjicostis, Christoforos N.; Keroglou, C. (Institute of Electrical and Electronics Engineers Inc., 2014)
      In many emerging security applications, a property of a system, that may reveal important details about its behaviour, needs to be kept secret (opaque) to outside observers (intruders). Motivated by such applications, ...
    • Conference Object  

      Opacity verification in stochastic discrete event systems 

      Saboori, A.; Hadjicostis, Christoforos N. (2010)
      Motivated by security and privacy considerations in applications of discrete event systems, various notions of opacity have been introduced. Specifically, a system is said to be current-state opaque if the entrance of the ...
    • Conference Object  

      Opacity-enforcing supervisory strategies for secure discrete event systems 

      Saboori, A.; Hadjicostis, Christoforos N. (2008)
      Initial-state opacity emerges as a key property in numerous security applications of discrete event systems including key-stream generators for cryptographic protocols. Specifically, a system is initial-state opaque if the ...
    • Article  

      Opacity-enforcing supervisory strategies via state estimator constructions 

      Saboori, A.; Hadjicostis, Christoforos N. (2012)
      State-based notions of opacity, such as initial-state opacity and infinite-step opacity, emerge as key properties in numerous security applications of discrete event systems. We consider systems that are modeled as partially ...
    • Conference Object  

      Probabilistic system opacity in discrete event systems 

      Keroglou, C.; Hadjicostis, Christoforos N. (Institute of Electrical and Electronics Engineers Inc., 2016)
      In many emerging security applications, a system designer frequently needs to ensure that a certain property of a given system (that may reveal important details about the system's operation) be kept secret (opaque) to ...
    • Article  

      Probabilistic system opacity in discrete event systems 

      Keroglou, C.; Hadjicostis, Christoforos N. (2018)
      In many emerging security applications, a system designer frequently needs to ensure that a certain property of a given system (that may reveal important details about the system’s operation) be kept secret (opaque) to ...
    • Conference Object  

      Reduced-complexity verification for initial-state opacity in modular discrete event systems 

      Saboori, A.; Hadjicostis, Christoforos N. (2010)
      In this paper, we propose and analyze reduced-complexity methodologies for verifying initial-state opacity in modular discrete event systems. Initial-state opacity requires that the membership of the system initial state ...
    • Conference Object  

      Verification of infinite-step opacity and analysis of its complexity 

      Saboori, A.; Hadjicostis, Christoforos N. (2009)
      In this paper, we formulate, analyze, and devise methodologies to verify the notion of infinite-step opacity in discrete event systems that are modeled as (possibly non-deterministic) finite automata with partial observation ...
    • Article  

      Verification of infinite-step opacity and complexity considerations 

      Saboori, A.; Hadjicostis, Christoforos N. (2012)
      We describe and analyze the complexity of verifying the notion of infinite-step opacity in systems that are modeled as non-deterministic finite automata with partial observation on their transitions. Specifically, a system ...
    • Conference Object  

      Verification of initial-state opacity in security applications of DES 

      Saboori, A.; Hadjicostis, Christoforos N. (2008)
      Motivated by security applications where the initial state of a system needs to be kept secret (opaque) to outside observers (intruders), we formulate, analyze and verify the notion of initial-state opacity in discrete ...
    • Article  

      Verification of initial-state opacity in security applications of discrete event systems 

      Saboori, A.; Hadjicostis, Christoforos N. (2013)
      In this paper, we formulate and analyze methodologies for verifying the notion of initial-state opacity in discrete event systems that are modeled as non-deterministic finite automata with partial observation on their ...
    • Conference Object  

      Verification of K-step opacity and analysis of its complexity 

      Saboori, A.; Hadjicostis, Christoforos N. (2009)
      In this paper, we analyze the verification of K-step opacity in discrete event systems that are modeled as (possibly non-deterministic) finite automata with partial observation on their transitions. A system is K-step ...
    • Article  

      Verification of K-step opacity and analysis of its complexity 

      Saboori, A.; Hadjicostis, Christoforos N. (2011)
      Motivated by security and privacy considerations in a variety of applications of discrete event systems, we describe and analyze the computational complexity required for verifying the notion of K-step opacity for systems ...