China’s National Quantum Lab Tests QKD on Maritime Logistics Channels in South China Sea

China Conducts First Maritime QKD Trials for Secure Cargo Route Communications

As China continued to accelerate its leadership in quantum technology during the mid-2010s, 2017 brought a new frontier to its national strategy: the maritime logistics domain.

On March 30, 2017, the National Laboratory for Quantum Information Science (NLQIS), in partnership with the Chinese Academy of Sciences and the Ministry of Transport, confirmed successful trials of quantum key distribution (QKD) on shipping routes in the South China Sea. The tests involved a hybrid system of quantum ground stations and satellite links relaying entangled photon pairs to cargo ships for ultra-secure communication.

This development marked a pioneering moment in quantum logistics, demonstrating the feasibility of real-time QKD over dynamic, high-latency maritime routes—an environment long considered hostile to quantum communication.

Background: Why Quantum in Shipping?

The maritime industry, particularly freight shipping, represents the backbone of global trade. It also presents a serious vulnerability for cybersecurity. Legacy satellite communication (SATCOM) systems, outdated shipboard IT infrastructure, and increasingly autonomous operations have made cargo fleets a tempting target for data interception, spoofing, and ransomware.

China’s growing focus on securing its Belt and Road Initiative (BRI), including its Maritime Silk Road corridor, drove the integration of quantum security principles into commercial logistics. With over 60% of China’s trade dependent on maritime shipping, safeguarding vessel-to-port communications became a national priority.

QKD provides a method for unbreakable encryption by transmitting entangled photon pairs. If intercepted, the quantum state collapses, instantly alerting users to the breach.

The March 2017 Trial

The QKD experiment involved:

• A shore-based quantum ground station located near Sanya, Hainan Province.

• A mobile QKD receiver installed aboard two COSCO-operated container ships operating near disputed maritime borders.

• A partial uplink through the Micius satellite (launched August 2016) for redundancy.

Entangled photons were generated on land, encoded using polarization protocols, and transmitted via adaptive free-space optical links to moving vessels at sea. Despite atmospheric scattering, saltwater humidity, and ship oscillation, the researchers achieved a 74.3% average photon detection fidelity at sea-level distances up to 120 kilometers.

Key Milestones and Outcomes

1. Secure Vessel Authentication:
   The experiment allowed vessels to receive unforgeable cryptographic credentials, authenticating their identities to port control authorities via a one-time pad encrypted using quantum keys.

2. QKD Performance Metrics:
   The team recorded key exchange rates of approximately 3.7 kbps over free-space maritime channels—sufficient for encrypting mission-critical data like container manifests, AIS override codes, and control software updates.

3. Hybrid Redundancy with Satellite QKD:
   To mitigate signal loss due to ocean wave interference, Micius was used as a failover entanglement source during one phase of the trial, further establishing a quantum-secured "air-sea-ground" communication chain.

4. Cybersecurity Proof-of-Concept for Supply Chains:
   In a simulated attack scenario, an attempted relay-based man-in-the-middle attack was detected in real-time due to the collapse of photon entanglement, showcasing the tamper-evident nature of QKD.

Strategic Implications for China and the Global Supply Chain

The trial had three major implications:

• Quantum Logistics as a Geopolitical Advantage:
  By integrating QKD into maritime supply chains, China positioned itself to offer ultra-secure port-to-vessel communication along BRI-aligned routes, potentially making its shipping ecosystem more attractive to security-conscious trading partners.

• Insurance and Risk Reduction:
  Quantum security could potentially lower insurance premiums for high-value cargo if proven at scale. Quantum-encrypted cargo tracking and manifest integrity reduce the risk of piracy, hacking, and cargo substitution fraud.

• Foundation for Autonomous Shipping:
  As autonomous ships begin to emerge, their control and communication systems become critical points of failure. A quantum-secured maritime communication framework paves the way for future unmanned vessels operating with safety and legal traceability.

Expert Perspectives

Dr. Jian-Wei Pan, lead researcher at NLQIS, noted:

“Maritime quantum communication is challenging, but not impossible. With this trial, we have demonstrated that moving platforms on the ocean can participate in entangled state transfer and secure key distribution—a milestone in quantum logistics.”

Captain Lu Hanchao, COSCO technical director, added:

“The days of radio-only ship communications are ending. What’s coming is an era where every cargo manifest, software update, or course command is secured by the laws of quantum physics.”

International Reactions

While Western nations remained cautious about full-scale maritime QKD, the European Union’s Horizon 2020 program began funding preliminary studies in 2018 on quantum-secured inter-port communications, citing the 2017 China trial as a proof-of-concept.

Japan’s Nippon Yusen Kaisha (NYK) and South Korea’s Hanjin Shipping also initiated early-stage partnerships with their national quantum labs following China's announcement.

By 2019, the International Maritime Organization (IMO) had issued a discussion paper exploring the regulatory and certification frameworks required for quantum-secured vessel communication.

Challenges and Limitations

Despite the promising results, significant hurdles remained:

• Weather Dependency:
  Optical QKD is vulnerable to heavy fog, rain, and wave-induced misalignment.

• Limited Bandwidth:
  QKD does not replace high-throughput satellite comms. It augments it with security layers.

• Hardware Miniaturization:
  Early QKD receivers required bulky stabilization rigs. Shipping-grade miniaturization remained a hurdle until mid-2020s.

Conclusion

The March 2017 maritime QKD trial conducted by China’s National Laboratory for Quantum Information Science marked a critical leap forward in quantum logistics. By extending quantum key distribution to oceanic supply chains, China demonstrated how quantum-secure communication could be brought to one of the world’s most vulnerable infrastructure domains: maritime shipping.

As global supply chains become increasingly autonomous, digitized, and geopolitically sensitive, quantum-encrypted communications offer both resilience and trust in high-risk regions. This trial wasn’t just about encryption—it was about redefining how nations and corporations think about information assurance at sea.

The long-term vision? A quantum logistics mesh that spans satellite, terrestrial, and maritime systems—entangling global trade itself in the next era of security.