Formal Verification of Digital Twins with TLA and Information Leakage Control

TL;DR

This paper introduces a formal verification methodology for digital twins using TLA, addressing uncertainties and information leakage, demonstrated on an UAV digital twin to ensure correct data synchronization.

Contribution

It presents a novel approach to specify and verify digital twins with formal guarantees, including controlled information leakage, using TLA and finite state machines.

Findings

Verified UAV digital twin synchronization

Controlled information leakage with formal guarantees

Applicable to complex distributed systems

Abstract

Verifying the correctness of a digital twin provides a formal guarantee that the digital twin operates as intended. Digital twin verification is challenging due to the presence of uncertainties in the virtual representation, the physical environment, and the bidirectional flow of information between physical and virtual. A further challenge is that a digital twin of a complex system is composed of distributed components. This paper presents a methodology to specify and verify digital twin behavior, translating uncertain processes into a formally verifiable finite state machine. We use the Temporal Logic of Actions (TLA) to create a specification, an implementation abstraction that defines the properties required for correct system behavior. Our approach includes a novel weakening of formal security properties, allowing controlled information leakage while preserving theoretical guarantees. We demonstrate this approach on a digital twin of an unmanned aerial vehicle, verifying synchronization of physical-to-virtual and virtual-to-digital data flows to detect unintended misalignments.