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arXiv · 1802.03321

Opacity of nondeterministic transition systems: A (bi)simulation relation approach

Kuize Zhang·Xiang Yin·Majid Zamani
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Abstract

In this paper, we propose several opacity-preserving (bi)simulation relations for general nondeterministic transition systems (NTS) in terms of initial-state opacity, current-state opacity, K-step opacity, and infinite-step opacity. We also show how one can leverage quotient construction to compute such relations. In addition, we use a two-way observer method to verify opacity of nondeterministic finite transition systems (NFTSs). As a result, although the verification of opacity for infinite NTSs is generally undecidable, if one can find such an opacity-preserving relation from an infinite NTS to an NFTS, the (lack of) opacity of the NTS can be easily verified over the NFTS which is decidable.

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Kuize Zhang, Xiang Yin, Majid Zamani. 2018-02-09. Opacity of nondeterministic transition systems: A (bi)simulation relation approach. https://arxiv.org/abs/1802.03321

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