How Long Does a Migration to a Quantum-Safe Network Take?

Quantum computers pose a growing threat to the security of modern networks. Classical encryption algorithms that are still secure today may in the future be broken by quantum hardware that is exponentially more powerful than current systems. In 2026, more and more organizations are taking their first steps toward a quantum-safe network, but the question on virtually everyone’s mind is: how long does such a migration actually take?

The honest answer is: it depends heavily on the complexity of your current infrastructure, the risk level of your data, and the scale of your organization. A migration to post-quantum encryption is not a weekend project, but with a clear approach and realistic planning, the process is manageable. In this guide, you will walk through the six steps that determine how long your network migration will take and how to execute it as smoothly as possible.

Map your current network security

Before you take a single step toward quantum-safe security, you need to know exactly what you have. Many organizations underestimate the extent of their cryptographic dependencies. Encryption is not only found in VPN connections or email, but also in certificates, key exchange, authentication protocols, and sometimes even in hardware.

1. Inventory all systems, connections, and applications that use encryption or digital signatures.
2. Identify which cryptographic algorithms are in use (such as RSA, ECC, or AES) and where they are implemented.
3. Document dependencies between systems so that you understand which adjustments have effects elsewhere.
4. Map out which data is most sensitive and which connections are business-critical.

After this inventory, you will have a complete picture of your current cryptographic landscape. The larger and more complex this landscape, the more time you must reserve for the next steps. Organizations with hundreds of systems and multiple locations can easily count on several weeks to a few months for this step alone. Want to know how sensitive data can be protected at the network level? It always starts with this step.

Determine the migration order based on risk level

Not everything needs to be migrated at once. A risk-based approach ensures that the most vulnerable and critical parts of your network are protected first. This significantly shortens the effective risk period, even if the full migration takes longer.

1. Classify your systems based on the sensitivity of the data they process or store.
2. Assess which connections have been active the longest and therefore carry the most risk from so-called “harvest now, decrypt later” attacks.
3. Prioritize systems that communicate via public networks or external parties.
4. Draw up a migration matrix: which system, when, and with what level of urgency.

A common mistake is starting with the simplest systems to achieve quick results. That feels good, but it leaves the biggest risks unprotected the longest. Start with what is most vulnerable, even if that is technically more challenging. Protection against quantum threats requires a deliberate choice in order, not just in technology.

Choose the right quantum-safe standards and solutions

In 2026, the first post-quantum standards from the American NIST have been officially established. This gives organizations a solid foundation to build on. Choosing the right standard and the associated solutions is a technical decision with long-term consequences, so take your time with it.

Relevant considerations when choosing standards and solutions:

• Choose algorithms that are included in the officially published NIST post-quantum standards.
• Consider hybrid encryption: a combination of classical and quantum-safe algorithms, so that you are protected during the transition period.
• Check whether your current hardware and software support the new algorithms, or whether replacement is necessary.
• Assess vendor support: are your current partners already working with quantum cryptography-compatible solutions?

We work with solutions from partners such as Nokia and Cisco, which are already actively focusing on quantum-resistant security at layer 1 and layer 2 of the OSI model. View our overview of encryption solutions for an impression of what is technically possible at the network level.

Plan the phasing and estimate the timeline realistically

A realistic timeline for a network migration to a quantum-safe environment varies greatly by organization. A smaller organization with a manageable infrastructure can complete the migration in six to twelve months. Larger organizations with complex, distributed networks are more likely to count on two to four years for a full transition.

1. Divide the migration into phases: inventory, pilot implementation, rollout per priority group, and validation.
2. Plan a pilot phase of at least four to eight weeks to test the chosen solutions in a controlled environment.
3. Reserve buffer time for unexpected compatibility issues, vendor delays, or changes in standards.
4. Align the planning with your operational calendar: avoid migrations during peak periods or critical business phases.

A common mistake is underestimating the testing phase. Quantum-safe algorithms behave differently from classical encryption, including in terms of computation time and key size. Test extensively before rolling out to production environments.

Execute the migration without operational disruption

The execution of the migration to a quantum-safe network is the moment where planning and practice meet. The goal is continuity: your network remains operational while security is renewed step by step.

1. Always implement changes first in a test environment that mirrors the production environment as closely as possible.
2. Use a hybrid approach during the transition period: run classical and quantum-safe encryption in parallel until all systems have been migrated.
3. Ensure a fallback plan for every system being migrated, so you can switch quickly in the event of problems.
4. Communicate changes in a timely manner to internal teams and external parties that depend on the relevant connections.

Operational disruption is the greatest risk in any network security migration. Good change management, clear communication, and a phased rollout are your best protection against it. Do you also want to maintain visibility into what is happening on your network during the migration? Real-time fiber optic monitoring helps you detect anomalies immediately.

Validate the quantum-safe configuration after implementation

After the rollout, the work is not yet done. Validation is an essential final step of every successful migration. Check not only whether the new encryption works technically, but also whether the security actually delivers the desired level of protection.

1. Conduct a technical audit on all migrated systems and connections to confirm that only quantum-safe algorithms are active.
2. Test performance: check whether latency, throughput, and system load remain within acceptable limits.
3. Have an independent party conduct a penetration test focused on the new cryptographic configuration.
4. Document the final configuration and establish a schedule for periodic revalidation, as standards and threats continue to evolve.

With a validated quantum-safe configuration, you have officially completed the migration. But do not treat it as an endpoint. Quantum-safe security is an ongoing process: new vulnerabilities are discovered, standards are tightened, and your network grows along with your organization. Make sure your monitoring and management are in order so that you always maintain an overview. Want to know more about how we support organizations in their security strategy? View our complete security offering.