Towards Provably Secure Encrypted Control Using Homomorphic Encryption

TL;DR

This paper introduces a new security framework for encrypted control systems that leverages homomorphic encryption to provide provable security guarantees against attacks, addressing gaps in existing cryptographic approaches.

Contribution

It proposes a novel security definition for encrypted control under attack and demonstrates how homomorphic encryption can enhance security in control systems.

Findings

Security of encrypted control can be formally proven using cryptographic methods.

Homomorphic encryption improves the security robustness of control systems.

The proposed security model bridges cryptography and control system security.

Abstract

Encrypted control is a promising method for the secure outsourcing of controller computation to a public cloud. However, a feasible method for security proofs of control has not yet been developed in the field of encrypted control systems. Additionally, cryptography does not consider certain types of attacks on encrypted control systems; therefore, the security of such a system cannot be guaranteed using a secure cryptosystem. This study proposes a novel security definition for encrypted control under attack for control systems using cryptography. It applies the concept of provable security, which is the security of cryptosystems based on mathematical proofs, to encrypted control systems. Furthermore, this study analyzes the relation between the proposed security and the conventional security of cryptosystems. The results of the analysis demonstrated that the security of an encrypted control system can be enhanced by employing secure homomorphic encryption.