Homomorphic Encryption for Secure Data Computations

Abstract

Encryption is the art of converting text messages into a secret code using a certain encryption key. Hundreds of years ago, people used to propose new encryption algorithms to secure their own data and protect their privacy. Unfortunately, once the data is encrypted, it would remain in its secret-useless form till a certain key is used to decrypt it. Homomorphic encryption is the kind of encryption that permits one to perform useful computations on encrypted data without decrypting them. The results of these computations are equivalent to the results of the similar computations done over the plain data. By this way, one could safely allow third parties to make useful computations over his own data without scarifying his privacy.

Building on the above description, the Thesis aims at exploring the efficiency of using homomorphic encryption techniques in solving real-world problems, in which computing over encrypted data is a must. Although homomorphic encryption includes two different categories; the fully homomorphic encryption techniques, and the partially homomorphic encryption ones, the Thesis focuses on the second category only. The reason behind this research direction is to avoid the high overheads associated with the usage of fully homomorphic encryption methods.

The Thesis is divided into six chapters, along with the table of contents, list of figures, list of tables, abbreviations, symbols, and the references.

The Thesis contents are presented hereafter.

Chapter 1 presents the introduction to the Thesis. It mainly highlights the motivation behind the