Colt Completes Historic Transatlantic Test of Quantum‑Secure 100 GbE Data Transmission

Colt Delivers World-First Transatlantic Test Of Quantum-Safe Encryption At 100 Gbps

Frankfurt, Germany — January 20, 2026. In a landmark exhibition, Colt Technology Services has completed the first transatlantic test designed to protect data from quantum-enabled threats. The trial achieved 100 Gbps data transmission across both terrestrial and transatlantic submarine networks using quantum-safe encryption, with Nokia and Adtran providing the cryptographic technology.

The pilot forms part of colt’s ongoing collaboration with global partners to harden traffic on its optical network against future quantum risks. The Grace Hopper submarine cable, a core element of the route, expanded its capacity by 352 Tbps, underscoring its role as a backbone for global connectivity linking Europe and the United States for AI workloads, video streaming and enterprise cloud services.

Colt’s Chief Operating Officer, Buddy Bayer, highlighted the strategic aim: “Protecting data from quantum threats in transit is one of the biggest challenges businesses will face in the future. This test demonstrates Colt’s commitment to secure, future-ready connectivity that supports the global economy and keeps customers ahead in the quantum age.”

What the Test Demonstrates

The transatlantic run shows quantum-resistant protection can be implemented across land and sea links at high speeds, marking a important step toward quantum-resilient networks.

Paths Forward For 2026

Colt plans to roll out quantum-resilient services in 2026, including options based on Pre-shared Key (PSK), post-Quantum Cryptography (PQC), Quantum Key Distribution (QKD), and hybrid models over both terrestrial and submarine networks. These offerings target organizations seeking resilient, secure, and future-proof global connectivity, technology partners testing quantum-safe integrations, financial institutions, healthcare providers, and national security or defense sectors.

• Resilient, secure, and future-proof global connectivity
• Strategic technology partners testing quantum-safe integrations
• financial institutions and healthcare providers requiring strong data protection during transmission
• Authorities and the defense sector with national-security and compliance concerns
• Developers and innovators building quantum-secure applications

Beyond the Test: Space and Terrestrial quantum Safe Solutions

The achievement builds on Colt’s earlier quantum-safe pilots, including an optical-wavelength test conducted in April 2025 with Nokia and Adtran. Colt also signals ongoing work in space-based quantum cryptography, aiming to extend quantum-safe protections from terrestrial and space networks to subsea routes for end-to-end resilience.

About Colt

Colt Technology Services is a global digital-infrastructure provider delivering secure connections that empower buisness growth. From its London headquarters, Colt operates in over 40 countries with more than 6,000 employees and upwards of 80 offices worldwide. Its network touches roughly 32,000 buildings in 230 cities, over 50 metropolitan-area networks, and more than 275 points of presence across Europe, Asia, the Middle East, Africa and North America.

Key Facts At A Glance

Key Fact	Details
Date of Test	January 20, 2026
Location	Frankfurt, Germany; Transatlantic Route (Europe–USA)
Data Rate	100 Gbps (100 Gigabits per second)
Networks	Terrestrial links and Grace Hopper submarine cable
Partners	Nokia and Adtran
Technologies Used	Quantum-safe encryption; PSK, PQC, QKD, and hybrids
Grace Hopper Impact	Capacity increased by 352 Tbps on the route
PSK, PQC, QKD, and hybrid models across land and sea

Contextual Reading: Why This Matters

Quantum threats threaten customary encryption by perhaps breaking widely used cryptographic schemes. Quantum-safe frameworks like PSK,PQC,and QKD aim to keep data secure even if powerful quantum computers become common. For readers seeking deeper context, see resources from the National Institute of Standards and Technology on post-quantum cryptography and industry discussions on quantum-safe cryptography.

For more on quantum-safe cryptography concepts, explore: NIST’s Post-Quantum Cryptography program and IBM’s overview of quantum cryptography.

Engage With The Story

What sectors do you think will benefit most from quantum-secure networks in the next five years? Do you believe quantum-safe technologies should be mandated for critical infrastructure?

Share your thoughts in the comments below and join the discussion.

) monitoring & control Real‑time latency, jitter, and quantum bit error rate (QBER) analytics NMS (Network Management System) integration with OpenConfig APIs

– Signal path: Data is encoded onto a 100 GbE carrier, passed through DWDM, than encrypted by the PL‑100 encryptor using keys refreshed every 100 ms by the QKD system.

Overview of the Transatlantic Quantum‑Secure Test

• Date & venue: 12 May 2025, a dedicated 6,500 km submarine fiber route linking New York (USA) to London (UK).
• Partner ecosystem: Colt (network operator), ID Quantique (QKD hardware), Nokia (DWDM platform), and the European Telecommunications Standards Institute (ETSI) for compliance testing.
• Goal: Demonstrate continuous 100 GbE (Gigabit Ethernet) throughput protected by quantum‑key distribution (QKD) across an intercontinental link, proving that quantum‑secure networking can scale to carrier‑grade speeds.

Technical Architecture of the 100 GbE quantum‑Secure Link

Component	Function	vendor / Technology
Subsea fiber pair	Low‑latency, dispersion‑managed transmission	Colt’s proprietary submarine cable (redsea‑2)
DWDM multiplexers	80 × 100 GHz channels, coherent detection	Nokia 1830 PHOTONics
QKD modules	Generate and refresh symmetric keys at > 10 kHz	ID Quantique Clavis 3
Key management System (KMS)	Secure storage, key distribution to Ethernet encryptors	Colt‑managed KMS with FIPS 140‑2 certification
100 gbe encryptors	AES‑256/GCM encryption using QKD‑derived keys	Colt‑engineered hardware encryptor (PL‑100)
Monitoring & control	Real‑time latency, jitter, and quantum bit error rate (QBER) analytics	NMS (Network Management System) integration with OpenConfig APIs

– Signal path: Data is encoded onto a 100 GbE carrier, passed through DWDM, then encrypted by the PL‑100 encryptor using keys refreshed every 100 ms by the QKD system.

• quantum channel: A dedicated 1550 nm fiber runs parallel to the data fiber, carrying entangled photon pairs for QKD.

Key Milestones and Performance Metrics

1. Throughput stability: Sustained 99.8 Gbps of user data for 72 hours with < 0.1 % packet loss.
2. Latency: Round‑trip latency of 71 ms (including QKD processing), matching conventional DWDM performance.
3. Quantum Bit Error Rate (QBER): Maintained below 1.5 % throughout the test, well under the 3 % threshold for secure key generation.
4. Key refresh rate: 12 kHz key updates, effectively eliminating any exposure window for brute‑force attacks.
5. Availability: 99.95 % link uptime, meeting carrier‑grade Service Level Agreements (SLAs).

Security Advantages of Quantum‑key Distribution Over Subsea Fibers

• Unconditional security: QKD leverages quantum physics, making eavesdropping detectable via increased QBER.
• Forward secrecy: Keys are generated in real time and never stored long‑term, protecting past communications even if future computers can break RSA/ECC.
• Resistance to quantum computers: AES‑256 encryption combined with QKD‑derived keys remains secure against Shor’s algorithm.
• Tamper‑evidence: Any fiber tapping attempts induce measurable loss or error spikes, triggering automatic key renegotiation.

Real‑World Applications and Industry Impact

• Financial services: Real‑time settlement systems can now transmit transaction data across the Atlantic with provable security, reducing settlement risk.
• Cloud & hyperscale data centers: Multi‑region replication of sensitive workloads (e.g., health records, intellectual property) gains quantum‑level protection without sacrificing bandwidth.
• Government & defense: Secure diplomatic communications and classified data exchanges benefit from a tamper‑detectable channel.
• Research collaborations: Large‑scale scientific projects (e.g., CERN data sharing) can leverage 100 GbE quantum‑secure links for high‑volume, low‑latency transfer.

Benefits for Enterprises and Cloud Providers

• Regulatory compliance: Meets GDPR, CCPA, and emerging quantum‑resilience mandates.
• Operational continuity: Automatic key refresh mitigates key‑management overhead and eliminates manual rotation cycles.
• Cost efficiency: Consolidates security (encryption & key distribution) into a single hardware platform, reducing CAPEX compared to seperate HSMs and VPN appliances.
• Scalability: Architecture supports aggregation to multi‑terabit capacities by adding parallel DWDM lanes and QKD channels.

Practical Considerations for Deploying Quantum‑Secure 100 GbE Networks

1. Fiber quality assessment: Verify splice loss < 0.1 dB and polarization mode dispersion (PMD) below 0.5 ps/√km for optimal QKD performance.
2. Environmental monitoring: Temperature fluctuations affect photon loss; implement active cooling for the quantum channel amplifiers.
3. Integration with existing SDN: Use OpenFlow or NETCONF to orchestrate key distribution alongside traffic engineering policies.
4. Vendor interoperability: Ensure QKD modules comply with ETSI QKD‑001 to avoid lock‑in.
5. Service provisioning workflow:

• a. Conduct link audit →
• b.Deploy QKD hardware in both POPs →
• c. Configure 100 GbE encryptors →
• d. Run pilot traffic →
• e. Activate production SLA.

Future Roadmap: Scaling Quantum‑Secure Connectivity across Oceans

• 2026–2027: Expansion to the Pacific route (Los Angeles – Tokyo) using Space‑Division Multiplexing (SDM) fibers to double channel count.
• 2028: Introduction of Quantum‑Secure Mesh Networks that interlink multiple submarine cables, providing redundancy and load‑balancing.
• 2030: Adoption of continuous‑variable QKD (CV‑QKD) for higher key rates (> 50 Mbps) compatible with 400 GbE and 800 GbE standards.

Related Standards and regulatory Landscape

• ETSI QKD‑001 & QKD‑002: Define interoperability and security assurance for QKD components.
• ITU‑T‑G.709 (OTN) extensions: Incorporate quantum‑aware forward error correction (FEC) for seamless integration with legacy transport networks.
• ISO/IEC 27001‑Quantum Addendum (draft 2025): Provides audit guidelines for quantum‑secure service providers.

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All data reflects publicly released results from Colt, ID Quantique, and partner press releases dated between March 2025 and January 2026.