Additive order preserving encryption based encrypted documents ranking in secure cloud storage

Abstract

Ranking the encrypted documents stored on cloud storage servers is important in encrypted information retrieval. Order preserving encryption (OPE) could be used to help ranking the encrypted documents. However, order preserving encryption schemes don't support additions over cipher texts. A new additive order preserving encryption is proposed. Both the cipher text and the sum of the cipher texts preserve orders. By summing up the encryptions of term weights, the relevance between encrypted documents and queries are obtained. According to the relevance the documents are ranked. Experimental results show that the proposed encryption scheme based ranking could achieve very good retrieval performance. © 2012 Springer-Verlag.