Title
Preserving differential privacy under finite-precision semantics.
Abstract
The approximation introduced by finite-precision representation of continuous data can induce arbitrarily large information leaks even when the computation using exact semantics is secure. Such leakage can thus undermine design efforts aimed at protecting sensitive information. We focus here on differential privacy, an approach to privacy that emerged from the area of statistical databases and is now widely applied also in other domains. In this approach, privacy is protected by adding noise to the values correlated to the private data. The typical mechanisms used to achieve differential privacy have been proved correct in the ideal case in which computations are made using infinite-precision semantics. In this paper, we analyze the situation at the implementation level, where the semantics is necessarily limited by finite precision, i.e., the representation of real numbers and the operations on them are rounded according to some level of precision. We show that in general there are violations of the differential privacy property, and we study the conditions under which we can still guarantee a limited (but, arguably, acceptable) variant of the property, under only a minor degradation of the privacy level.
Year
DOI
Venue
2013
10.1016/j.tcs.2016.01.015
Theoretical Computer Science
Keywords
Field
DocType
floating point arithmetic,differential privacy
Data mining,Computer science,Floating point,Privacy Level,Theoretical computer science,Information sensitivity,Real number,Computation,Discrete mathematics,Combinatorics,Differential privacy,Arbitrarily large,Semantics
Journal
Volume
Issue
ISSN
655
PB
0304-3975
Citations 
PageRank 
References 
8
0.55
14
Authors
3
Name
Order
Citations
PageRank
Ivan Gazeau1182.08
Dale Miller22485232.26
Catuscia Palamidessi32876184.08