On privacy preserving encrypted data stores

Abstract

Bucketization techniques allow for effective organization of encrypted data at untrusted servers and for querying by clients. This paper presents a new metric for estimating the risk of data exposure over a set of bucketized data. The metric accounts for the importance of bucket distinctness relative to bucket access. Additionally, we review a method of controlled diffusion which improves bucket security by maximizing entropy and variance. In conjunction with our metric we use this method to show that the advantages of bucketization may be offset due to a loss of bucket security. © 2013 Springer Science+Business Media Dordrecht(Outside the USA).