Further methods for encrypted linear dynamic controllers utilizing re-encryption

TL;DR

This paper introduces two improved methods for encrypted linear dynamic controllers using re-encryption, reducing communication and computational costs while maintaining secure operations with homomorphic encryption.

Contribution

It proposes novel re-encryption-based techniques that enhance efficiency in encrypted control systems, addressing computational and communication challenges.

Findings

Reduced communication effort in encrypted control

Lower computational burden for controller operations

Maintained security with homomorphic encryption

Abstract

Homomorphic encryption (HE) applied to a networked controller enables secure operation, but in most cases it allows for addition and multiplication over integers only, because of computation efficiency. Several related results deal with such constraints by means of re-encrypted controller output, based on which the controller can be re-constructed and operate over integers. This paper presents two modified methods based on the output re-encryption, which will further reduce the required communication effort and computational burden, respectively.