A FHE-based evaluation for searching on encrypted data

Abstract

The model based on cloud computing provides considerable advantages of cost-quality regarding the access to a range of IT services. The cloud providers must ensure solid security guarantees. One of the critical issues is that of privacy and access rights to data migrated and managed by the cloud. In this sense, one solution is based on encrypting data before its upload in cloud. In this paper we propose a solution to the problem of searching on encrypted data. Our proposal is based on FHE cryptography and allows searching an integer within a set of encrypted values. The search algorithm can be processed on an untrusted entity (e.g. a service in the cloud), it does not require decrypting the data on the server nor intermediary exchanges with the decryption key holder (e.g. the cloud service client). We show a practical implementation for our solution. Experimental results are also presented.