Input-Output History Feedback Controller for Encrypted Control with Leveled Fully Homomorphic Encryption. (arXiv:2109.10718v2 [eess.SY] UPDATED)

Protecting the parameters, states, and input/output signals of a dynamic
controller is essential for securely outsourcing its computation to an
untrusted third party. Although a fully homomorphic encryption scheme allows
the evaluation of controller operations with encrypted data, an encrypted
dynamic controller with the encryption scheme destabilizes a closed-loop system
or degrades the control performance due to overflow. This paper presents a
novel controller representation based on input-output history data to implement
an encrypted dynamic controller that operates without destabilization …

computation control data dynamic encrypted encrypted data encryption evaluation feedback fully homomorphic encryption history homomorphic encryption input operations outsourcing party protecting signals states third untrusted