A framework for quantum-secure communications in cyber-physical control systems with experimental demonstration in...

Area of Science:

• Cybersecurity
• Quantum Information Science
• Control Systems Engineering

Background:

• Quantum key distribution (QKD) provides security based on quantum mechanics, ideal for critical infrastructure.
• Integrating QKD into safety-critical systems faces challenges in latency, key availability, and stability.
• Current QKD applications are mainly in lab or network settings, not yet in real-time control systems.

Purpose of the Study:

• To introduce and experimentally demonstrate a QKD-secured framework for safety-critical cyber-physical systems.
• To validate the framework's ability to meet stringent requirements for low-latency, real-time operation.
• To establish a universal approach for quantum cybersecurity in critical infrastructure.

Main Methods:

• Developed a QKD-secured data acquisition and control framework.
• Deployed a phase-encoding decoy-state BB84 system on Purdue's 10 kWth digital research reactor (PUR-1).
• Evaluated performance with One-Time Pad (OTP), AES-256, and ASCON cryptographic schemes.

Main Results:

• Achieved real-time encryption/decryption of 2,000 reactor signals.
• Demonstrated a stable secret-key rate of 320 kbps at 54 km with a 3.8% quantum bit error rate.
• Validated secure communication up to 82 km (OTP) and 140 km (AES-256), supporting real-time operation.

Conclusions:

• The developed framework enables secure, low-latency, real-time operation in safety-critical environments.
• Quantum communication technologies can be integrated into nuclear reactors and other critical infrastructure.
• This work establishes a universal framework for quantum cybersecurity in safety-critical systems.