Keeping Secrets in Possibilistic Knowledge Bases with Necessity-Valued Privacy Policies
نویسنده
چکیده
Controlled Query Evaluation (CQE) is a logical framework for the protection of secrets in databases. In this article, we extend the CQE framework to possibilistic logic: knowledge base, a priori knowledge and privacy policy are expressed with necessity-valued formulas that represent several degrees of certainty. We present a formal security de nition and analyze an appropriate controlled evaluation algorithm for this possibilistic case.
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