Fuzzy Private Matching (Extended Abstract) [article]

Łukasz Chmielewski, Jaap-Henk Hoepman
2007 arXiv   pre-print
In the private matching problem, a client and a server each hold a set of n input elements. The client wants to privately compute the intersection of these two sets: he learns which elements he has in common with the server (and nothing more), while the server gains no information at all. In certain applications it would be useful to have a private matching protocol that reports a match even if two elements are only similar instead of equal. Such a private matching protocol is called fuzzy, and
more » ... is useful, for instance, when elements may be inaccurate or corrupted by errors. We consider the fuzzy private matching problem, in a semi-honest environment. Elements are similar if they match on t out of T attributes. First we show that the original solution proposed by Freedman et al. is incorrect. Subsequently we present two fuzzy private matching protocols. The first, simple, protocol has bit message complexity O(n Tt (T |D|+k)). The second, improved, protocol has a much better bit message complexity of O(n T (|D|+k)), but here the client incurs a O(n) factor time complexity. Additionally, we present protocols based on the computation of the Hamming distance and on oblivious transfer, that have different, sometimes more efficient, performance characteristics.
arXiv:0710.5425v1 fatcat:dkblydoa7venppbfw6jgyzyyp4