# QUANTUM SECURE NETWORKING
The emergence of quantum computing represents a direct threat to traditional encryption mechanisms that currently safeguard data-in-transit. Cyber adversaries are already believed to be harvesting encrypted data today in anticipation of decrypting it once quantum capabilities mature—an approach known as Harvest Now, Decrypt Later (HNDL). Given the rapid pace of progress toward Cryptographically Relevant Quantum Computers (CRQCs), the window to fully deploy quantum-secure networks is narrowing.
Regulatory frameworks such as GDPR, NIS2 and DORA now mandate stronger protection for data-in-transit, making quantum secure solutions a strategic priority and executive mandate for enterprises in finance, government, healthcare, and critical infrastructure. Governments worldwide are accelerating investments in Quantum‑Secure Networking and introducing mandates to retire classical encryption in favour of Post‑Quantum Cryptography (PQC). This shift is driven by rising regulatory pressure, increasing focus on data‑in‑transit protection and data sovereignty, and the growing harvest‑now, decrypt‑later (HNDL) threat.
Colt is strategically positioned as a leader in quantum‑era innovation, powered by Europe’s largest intelligent network, agile NaaS capabilities, and the trust of some of the world’s most data‑sensitive organizations. Our groundbreaking work in quantum‑secure networking has earned Colt several prestigious industry awards i.e. Gartner Eye on Innovation Award 2025, World Communication Network Evolution Award 2025, reinforcing our reputation as a frontrunner in Quantum Security and validating our commitment to securing the networks of the future.
Colt is embedding multi-layer defence approach combining PSK, PQC & QKD for quantum security into its network, to make it resilient against emerging threats as we scale globally. Colt’s Quantum Secure Networking (QSN) solution will deliver carrier grade protection for data in transit through multi-layer defence approach. Colt recommends the following solution to our customer to protect their data against the threat posed by Quantum computers:
**•** Implement PSK (Pre Shared Key) as a pragmatic starting point as an easy and cost-effective solution.
**•** Implement PQC across all connectivity products to meet regulatory mandates (NIS2, DORA, GDPR) and ensure resilience.
**•** Develop an advanced QKD portfolio for customers with highly sensitive data and long-term confidentiality requirements.
**•** Unified key management across all technologies/ network layers.
Colt envisage that its customers will prioritize migration to NIST-compliant PQC at the beginning, while later move into a multi-layer defence approach i.e. combination of PQC and QKD.
At the beginning of 2025, Colt conducted an innovative live-network trial evaluating QKD, PSK, and PQC technologies across both our metro and long-haul infrastructure. Towards the end of 2025, Colt also became the first provider to demonstrate a quantum‑secure network trial using NIST‑approved PQC algorithms between London and New York, spanning 6,500 km.
As it is widely understood, the laws of physics limit QKD transmission distance to approximately 100km, necessitating trusted nodes to extend reach. This is not viable across subsea and ultra long-distance networks. Consequently, satellite‑based QKD represents an important area for future exploration. Colt is currently collaborating with its suppliers and space agencies to conduct a QKD over Satellite trial towards the beginning of 2027.
We are not limiting our efforts to only trial activities; we are actively progressing toward delivering quantum secure networking solutions to our customers. This journey began last year, and we are on track to launch our product portfolio this year, incorporating QKD, PSK, and PQC technologies in phased releases.
Following the completion of our QKD‑over‑satellite trial, we will undertake a comprehensive evaluation of the results. Subject to a successful outcome, we plan to introduce our satellite‑enabled QKD offering toward the end of 2027 or early 2028.
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