In a centralized setting, the declarative nature of SQL is a major strength: a user can simply describe what she wants to retrieve, and need not worry about how the resulting query plan is actually generated and executed. However, in a decentralized setting, two query plans that produce the same result might actually reveal vastly different information about the intensional description of a use...

Recently, privacy preservation has become one of the key issues in data mining. In many data mining applications, computing frequencies of values or tuples of values in a data set is a fundamental operation repeatedly used. Within the context of privacy preserving data mining, several privacy preserving frequency mining solutions have been proposed. These solutions are crucial steps in many pri...

Broadcast encryption is a type of encryption where the sender can choose a subset from a set of designated receivers on the fly and enable them to decrypt a ciphertext while simultaneously preventing any other party from doing so. The notion of private broadcast encryption extends the primitive to a setting where one wishes to thwart an attacker that additionally attempts to extract information...

Privacy is crucial in many applications of machine learning. Legal, ethical and societal issues restrict the sharing of sensitive data making it difficult to learn from datasets that are partitioned between many parties. One important instance of such a distributed setting arises when information about each record in the dataset is held by different data owners (the design matrix is “vertically...

Differential privacy (DP) is a well-studied notion of privacy, that is generally achieved by randomizing outputs to preserve the privacy of the input records. A central problem in differential privacy is how much accuracy must be lost in order to preserve input privacy? We study this question in the context of distributed two-party differentially private protocols, where the input is split betw...

This position paper first summarizes work done by the first author on location privacy and differential privacy. These techniques will help to solve privacy problems in decentralized mobile social networks, which is the main theme of his PhD research. The paper then briefly reviews the state-of-the-art in privacy-preservation of social graphs and clarifies the lack of attention to graph sharing...

This paper considers a cloud computing setting in which similarity querying of metric data is outsourced to a service provider. The data is to be revealed only to trusted users, not to the service provider or anyone else. Users query the server for the most similar data objects to a query example. Outsourcing offers the data owner scalability and a low-initial investment. The need for privacy m...

privacy in the context of islamic law, the quran and sunnah reasons, is not mentioned. but this does not mean that the concept of privacy as one of the basic human rights in islamic law has not been considered. various aspects of privacy are presented in the sharia particular discourse. in this study in addition to concept of privacy and law in islamic law, law enforcement in islamic law and so...

Online privacy is an issue of increasing national importance, and voluntary privacy seals provided by third-party organizations such as TRUSTe and BBBOnline have been proposed as a means of assuring consumer privacy. Few studies have examined privacy seal effects. This study presents results of an online experiment that evaluated consumer response to privacy seals in a naturalistic exposure set...