Confidential procedure model: a method for quantifying confidentiality leakage

In this paper, we propose a theoretical-information Confidential Procedure Model (CPM) to quantify confidentiality (or information leakage). The advantages of the CPM model include the following: 1) confidentiality loss is formalized as a dynamic procedure, instead of a static function, and described via the "waterfall" diagram; 2) confidentiality loss is quantified in a relative manner, i. e., taken as a quantitative metric, the ratio of the conditional entropy being reserved after observing the entropy of the original full confidential information; 3) the optimal attacks including exhaustive attacks as well as all possible attacks that have (or have not even) been discovered, are taken into account when defining the novel concept of the confidential degree. To elucidate the proposed model, we analyze the information leakage in side-channel attacks and the anonymity of DC-net in a quantitative manner.