A New Anonymity Measure Based on Partial Entropy

With the development of Internet applications, a number of anonymous communication systems have been realized to protect the identity of communication participants. Therefore, it is essential to give a theoretically based and practically usable objective numerical measure for the provided level of anonymity. In this paper some typical anonymity measures are analyzed and limitations of these measures was highlighted. Then a new anonymity measure based on partial entropy is proposed, in which the anonymity is measured by using the entropy of the probability distribution of some distinct subjects in anonymity set. The results of analysis and calculation show that the new measure is preferable for anonymity evaluation.