Computation and Search over Encrypted XML Documents

The need for privacy-protected searching has garnered increasing interest as industries continue to adopt cloud technologies. Much of the recent efforts have been towards incorporating more advanced searching techniques. Although many have proposed solutions for search and computations in unencrypted data, developing efficient solutions over encrypted documents remains difficult. In this paper, we investigate the problem of processing a large amount of encrypted documents in XML-like formats where a user may wish to search or compute based on certain elements in the XML tree. Our solution makes use of index tables to allow for fast keyword and location queries. To allow computations to be performed on an untrusted server, homomorphic encryption is proposed and used in conjunction with symmetric encryption to reduce computational and storage cost.