Cryptology ePrint Archive: Report 2011/141

Fast and Private Computation of Cardinality of Set Intersection and Union

Emiliano De Cristofaro and Paolo Gasti and Gene Tsudik

Abstract: In many everyday scenarios, sensitive information must be shared between parties without complete mutual trust. Private set operations are particularly useful to enable sharing information with privacy, as they allow two or more parties to jointly compute operations on their sets (e.g., intersection, union, etc.), such that only the minimum required amount of information is disclosed. In the last few years, the research community has proposed a number of secure and efficient techniques for Private Set Intersection (PSI), however, somewhat less explored is the problem of computing the magnitude, rather than the contents, of the intersection -- we denote this problem as Private Set Intersection Cardinality (PSI-CA). This paper explores a few PSI-CA variations and constructs several protocols that are more efficient than the state-of-the-art.

Category / Keywords: Privacy-preserving set operations

Publication Info: CANS 2012

Date: received 21 Mar 2011, last revised 2 Oct 2012

Contact author: edecrist at uci edu

Available formats: PDF | BibTeX Citation

Note: This version presents modified constructions and new security model/proofs.

Version: 20121002:231903 (All versions of this report)

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