When datasets are distributed on different sources, finding out matched data while preserving the privacy of the datasets is a widely required task. In this paper, we address two matching problems against the private datasets on N (N ≥ 2) parties. The first one is the Privacy Preserving Set Intersection (PPSI) problem, in which each party wants to learn the intersection of the N private dataset...

This paper focuses on the relationship between an $L$-subset and the system of level-elements induced by it, where the underlying lattice $L$ is a complete residuated lattice and the domain set of $L$-subset is an $L$-partially ordered set $(X,P)$. Firstly, we obtain the sufficient and necessary condition that an $L$-subset is represented by its system of level-elements. Then, a new representat...

The problem of private information retrieval with private side information (PIR-PSI) is recently introduced by Kadhe et al. In this problem, N replicated databases each store K messages, of which M are known to the user as side-information. The identity of these M messages is unknown to the databases. The user wishes to retrieve, as efficiently as possible, a new desired message without reveali...

Secure computation has the potential to completely reshape the cybersecruity landscape, but this will happen only if we can make it practical. Despite significant improvements recently, secure computation is still orders of magnitude slower than computation in the clear. Even with the latest technology, running the killer apps, which are often data intensive, in secure computation is still a mi...

We study the basic operation of set union in global model differential privacy. In this problem, we are given a universe $U$ items, possibly infinite size, and database $D$ users. Each user $i$ contributes subset $W_i \subseteq U$ items. want an ($\epsilon$,$\delta$)-differentially private algorithm which outputs $S \subset \cup_i W_i$ such that size $S$ is as large possible. The problem arises...

We present an efficient protocol which, under certain assumptions, provides a suitable level of security and anonymity in the ideal cipher model when computing the intersection of two private data-sets containing lists of elements from a large domain. The assumptions are that each node is pre-loaded with a set of pseudonyms, signed by the network’s trusted authority; that the cardinality of eac...

In this work, we consider the Intersection-Sum problem: two parties hold datasets containing user identifiers, and the second party additionally has an integer value associated with each user identifier. The parties want to learn the number of users they have in common, and the sum of the associated integer values, but “nothing more”. We present a novel protocol tackling this problem using Diff...

In this paper, we defined a new secure multi-party computation problem, called Oblivious Set-member Decision problem, which allows one party to decide whether a secret of another party belongs to his private set in an oblivious manner. There are lots of important applications of Oblivious Set-member Decision problem in fields of the multi-party collaborative computation of protecting the privac...