LONDON, December 03, 2025 -- Arqit Quantum Inc., a global leader in quantum-safe encryption, and Sparkle, a Tier 1 global telecoms operator, have successfully demonstrated quantum-resilient data transmission across Sparkle’s optical network in Greece.

The proof of concept (POC), implemented over Sparkle metropolitan optical ring in Athens, shows how Arqit’s encryption technology can be embedded directly into the optical transport layer, protecting high-capacity networks against future quantum threats without impacting performance.

Sparkle validated that sensitive data can be secured at the physical network layer without compromising performance. Following the deployment of Arqit’s technology, end-to-end encryption was successfully applied to multi-100G optical links. This demonstrated that quantum-resistant protection can be delivered at the speed of light, ensuring ultra-secure data transmission without compromising performance.

Key Highlights:

• Optical-Layer Quantum-Safe Encryption: Sparkle’s Quantum-Safe over Internet (QSI) solution operates directly on optical transponders, integrating Arqit SKA-Platform encryption into the physical layer (L1).
• High-Capacity and Scalable: supports multi-100G optical links and scales with growing network demands.
• No physical changes to optical hardware: offers a practical, ready-to-deploy solution that doesn’t require expensive optical hardware changes. The quantum-safe symmetric encryption key was injected from VM and universal CPE appliances, connected to ETSI14 Interface and managed via the Orchestration platform.

Advancing Quantum-Safe Network Innovations:

This collaboration marks a significant step toward securing next-generation telecoms infrastructure. By combining Sparkle’s QSI leadership, Arqit’s quantum-safe encryption, and high-performance optical capabilities, the project demonstrates a scalable, real-world solution for quantum-resistant optical networking. This lays the groundwork for more resilient data networks worldwide.

“Securing the world’s data networks against emerging threats requires solutions that are both effective and practical,” said Andy Leaver, CEO of Arqit. “Telecom operators are looking for proven, low-disruption paths to quantum-safe security, and this POC demonstrates a ready-now path. It shows that quantum-safe encryption can be embedded directly into existing optical infrastructure, protecting high-capacity data links without disrupting performance or operations.”