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The dark side of timed opacity.


Franck Cassez



In this paper we extend the notion of opacity, defined for discrete-event systems, to dense-time systems. We define the timed opacity problem for timed automata and study its algorithmic status. We show that for the very restrictive class of Event Recording Timed Automata, the opacity problem is already undecidable leaving no hope for an algorithmic solution to the opacity problem in dense-time.

BibTeX Entry

    publisher        = {Springer},
    author           = {Cassez, Franck},
    month            = jun,
    editor           = {{Prof. J. H. Park et al.}},
    year             = {2009},
    keywords         = {timed automata, security, opacity},
    title            = {The Dark Side of Timed Opacity.},
    booktitle        = {Proc. of the 3rd International Conference on Information Security and Assurance (ISA'09)},
    pages            = {21--30},
    address          = {Seoul, Korea}


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