ACiS: Lightweight and Robust Homomorphic Block Cipher Additive Scheme

Abstract

Recent IoT emerging systems and applications require processing over encrypted data to preserve confidentiality. However, designing efficient Homomorphic Encryption (HE) algorithm to respond better to real-time requirements of IoT applications and tiny IoT devices is primordial. Unfortunately, existing homomorphic asymmetric schemes do not provide the efficiency implementation. While, on the other hand, homomorphic symmetric approaches suffer from a low level of security. In this paper, an efficient flexible additive homomorphic symmetric cipher scheme is proposed and it is called “ACiS”. Moreover, ACiS is based on the dynamic key approach to reach a high level of security, where different cryptographic primitives are used for different sessions. In addition, it can achieve a good performance and robustness against confidentiality attacks. It is based on a simple round function that should be iterated for nr iterations and <tex xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">$nr &gt; 1$</tex> . Furthermore, the proposed solution is analyzed and evaluated in terms of security and performance levels. Experimental results prove that the proposed solution reaches a good balance between performance and security level compared to the Paillier cipher scheme (a well-known asymmetric additive HE scheme).