Introduction

As the quantum computing era approaches, organisations must adopt Post-Quantum Cryptography (PQC) to safeguard their data against future quantum threats. A critical decision in this transition is whether to implement PQC through cloud-based services or rely on local deployment. Each approach offers distinct advantages and challenges, and the right choice depends on the organisation’s specific needs, infrastructure, and long-term goals.

The answer to this question is not as simple as one may think; many will think, for example, that local deployment is inherently more secure and performant. However, this isn’t necessarily the case for everyone. Listed below are pros for each solution, which would be prudent to consider when choosing what solution to go with for implementing PQC.

Why Cloud-Based PQC Might Be the Better Option

Performance Optimisation
PQC algorithms are computationally intensive due to their reliance on complex mathematical structures like lattices. These computations can strain local resources, especially for smaller organisations or devices with limited computational capacity. Cloud-based PQC offloads this processing to powerful, specialised servers, freeing up local resources for other critical tasks. This ensures faster encryption and decryption processes without compromising performance.

Enhanced Security
When using cloud-based PQC, the responsibility for maintaining robust, up-to-date security lies with the specialised provider. These providers continuously monitor emerging threats, apply the latest patches, and implement rigorous security protocols. This alleviates the burden on organisations that may lack the in-house expertise or resources to manage PQC security comprehensively.

Scalability
Cloud solutions are inherently scalable, allowing organisations to adjust their usage as needed without significant upfront investment. Whether you’re encrypting a small database or securing communications for millions of users, cloud-based PQC can scale effortlessly to meet your needs. This flexibility is invaluable for businesses anticipating growth or fluctuating workloads.

Ease of Integration and Updates
Cloud-based PQC providers offer streamlined integration via APIs or software development kits, reducing the complexity of deployment. Additionally, these services can roll out algorithm updates or new security features seamlessly, ensuring that your encryption remains cutting-edge without requiring manual updates on your end.

Why Local PQC Might Be the Better Option

Complete Data Control
For organisations handling highly sensitive data—such as government agencies, financial institutions, or healthcare providers—keeping cryptographic processes local ensures complete control over data. This eliminates concerns about transmitting sensitive information to external servers, reducing the risk of data interception.

Compliance and Regulatory Needs
Certain industries or jurisdictions have strict data sovereignty laws requiring that sensitive information remain within specific geographic boundaries. Local PQC implementation ensures compliance with such regulations, avoiding potential legal complications.

Reduced Latency
Cloud-based PQC introduces latency as data travels to and from remote servers. For applications requiring real-time responses, such as financial trading or emergency services, local PQC eliminates these delays, providing faster encryption and decryption.

Customisability
Local deployments can be tailored to meet unique organisational needs. Whether it’s integrating PQC into existing infrastructure or customising algorithms for specific use cases, local solutions offer a level of flexibility that cloud services may not always match.

So Which One Is Right?

Ultimately, it depends on your company’s circumstances, size and resources. Overall, both approaches are sound and have their use cases. But when it comes to the best approach for your specific situation, the rule of thumb is:

• Cloud-Based PQC is ideal for organisations seeking scalability, performance, and simplicity, particularly those without dedicated cryptography teams.
• Local PQC is better suited for entities with stringent compliance requirements, sensitive data, or real-time processing needs.

Some organisations may find that a hybrid approach—leveraging cloud services for certain applications while maintaining local control for others—offers the best of both worlds. However, this type of coordination requires some extensive thinking before undertaking the approach, and its use cases are quite narrow, as most companies might prefer to pick one lane or the other.

Conclusion

Post-Quantum Cryptography is no longer a distant concern but a pressing necessity for future-proofing your organisation’s security. Whether cloud-based or local, adopting PQC is essential to staying ahead of quantum threats. Evaluate your organisational needs carefully, and choose the solution that best aligns with your operational, security, and compliance goals.