The encryption protecting your organisation's most sensitive data — financial records, customer information, intellectual property, strategic communications — was never designed to withstand the processing power of a quantum computer. And while a full-scale, cryptographically relevant quantum computer (CRQC) doesn't exist yet, the window for IT teams to act is already closing. Fast.

This isn't a theoretical future problem. It's a present-day operational risk that demands a clear-headed, strategic response. This post breaks down exactly what quantum-resistant encryption is, why the threat is more urgent than most IT teams realise, what the regulatory landscape looks like right now, and — most importantly — what concrete steps you should be taking today.

Why Your Current Encryption Is at Risk

Most of the internet's security infrastructure is built on two families of algorithms: RSA and Elliptic Curve Cryptography (ECC).

The encryption protecting most of the internet is expected to become vulnerable to sufficiently advanced quantum computers — RSA and elliptic curve cryptography, which secure online banking, email, cloud storage, and messaging systems, rely on mathematical problems that quantum algorithms are designed to solve more efficiently.

The specific culprit is Shor's algorithm.

Shor's algorithm, published in 1994, shows that a large-scale fault-tolerant quantum computer could factor the integers behind RSA and solve the discrete logarithm problems used in elliptic curve systems.

In plain English: the maths problem that makes RSA and ECC practically unbreakable for classical computers becomes trivial for a quantum machine.

RSA encryption, used in secure email, VPNs, secure web connections (HTTPS), and software signing, is completely vulnerable to Shor's algorithm — RSA keys of any practical length, including 1024-bit, 2048-bit, or 4096-bit, can be broken by a sufficiently large quantum computer. Elliptic Curve Cryptography (ECC), including ECDSA and ECDH, is similarly vulnerable.

For IT security architects, the implication is stark. Your VPN tunnels, TLS handshakes, PKI infrastructure, code-signing pipelines, and digital certificates are all built on foundations that a quantum computer will eventually shatter.

The "Harvest Now, Decrypt Later" Threat Is Active Today

Here's where the urgency becomes impossible to dismiss: you don't need to wait for quantum computers to exist before the damage begins.

The quantum computing threat to enterprise cryptography is not a forecast — it is an ongoing operation. The attack pattern known as "Harvest Now, Decrypt Later" (HNDL) describes a strategy, well-documented by Western intelligence agencies and national cybersecurity authorities, in which adversaries systematically intercept and archive encrypted data today, holding it in reserve against the day when CRQCs can be used to break that encryption retroactively.

What makes enterprise businesses particularly vulnerable to HNDL attacks is the long-term value of their data. Sensitive customer information, proprietary research, and intellectual property can remain relevant and valuable for decades. If this data is harvested today, the damage caused by its exposure — even many years later — could be catastrophic.

The UK's NCSC has noted that state actors are conducting data theft campaigns "for exploitation in years to come." Five Eyes partner agencies have said the same thing in coordinated joint advisories. The attack is not theoretical — the collection phase is present-tense.

For industries like defence contracting, financial services, healthcare, and critical infrastructure, this threat is especially acute.

Critical infrastructure operators — including energy, utilities, and transportation — maintain architectural diagrams, operational technology configurations, and control system communications that, if decrypted later, could enable sabotage or disruption.

The NIST Standards Are Ready — And Waiting for You to Use Them

The good news is that the standardisation work is largely done. IT teams are not waiting on the science; the algorithms are published, tested, and available now.

In August 2024, NIST finalised three post-quantum cryptography standards: FIPS 203 (ML-KEM for key encapsulation), FIPS 204 (ML-DSA for digital signatures), and FIPS 205 (SLH-DSA for hash-based signatures). In March 2025, HQC was selected as an additional key encapsulation mechanism.

These standards provide the algorithmic foundation for quantum-safe cryptography migration worldwide, and most organisations should start with PQC migration since it can be deployed on existing infrastructure through software and firmware updates.

This is a critically important point — you don't need new hardware to start migrating. It's predominantly a software and configuration effort.

These post-quantum encryption standards secure a wide range of electronic information, from confidential email messages to e-commerce transactions that propel the modern economy. NIST is encouraging computer system administrators to begin transitioning to the new standards as soon as possible.

What the Regulatory Landscape Looks Like

Compliance pressure is building globally, and IT teams that treat this as optional will face regulatory consequences.

In response to the June 2025 Executive Order 14306, "Sustaining Select Efforts to Strengthen the Nation's Cybersecurity," CISA is providing and regularly updating lists to aid in post-quantum cryptography adoption.

The European Union has mandated that organisations define transition plans to PQC by the end of 2026, with implementation required in high-risk areas by 2030.

Financial services firms face even tighter sector-specific pressure:

Visa and Mastercard have both indicated EMV cryptogram protocol upgrades to PQC-ready algorithms on a phased timeline through 2028, with HSM and acquirer migration commencing in 2026. SWIFT's Customer Security Programme will incorporate PQC-readiness attestations into the 2027 attestation cycle.

NIST Interagency Report 8547 has established a formal deprecation timeline calling for the disallowance of RSA and elliptic curve cryptography across NIST standards by 2035.

The Migration Gap: Why You're Running Out of Time

Even with standards in hand, the migration timeline is daunting.

Post-quantum cryptography migration is a complex, multi-year undertaking. Unlike past transitions such as AES, SHA-2, and TLS 1.3, PQC migration requires larger parameter sizes, hybrid cryptographic schemes, and unprecedented ecosystem coordination.

Previous cryptographic migrations have taken five to ten years to complete. Waiting until quantum risks are being reported guarantees a long period of exposure.

Cryptography-discovery exercises at institutions that have run them tell a consistent story: roughly 60–80% of in-scope cryptographic inventory is undocumented, embedded in legacy applications or third-party libraries, or controlled by HSMs whose firmware paths to PQC are vendor-dependent.

Institutions that begin discovery in 2026 typically have a viable path to substantial completion by the 2030 backstop. Institutions that begin in 2028 generally do not. The migration is sequential — discovery, then crypto-agility framework, then algorithm replacement, then key-and-certificate rotation — and each stage materially constrains the next.

The message is clear: the bottleneck isn't the algorithms. It's your organisation's ability to find, document, and replace all of the places where vulnerable cryptography lives.

Building Crypto-Agility: The Strategic Foundation

Longer-term, the goal is not simply to swap RSA for ML-KEM. The goal is to build an organisation that can adapt its cryptographic posture quickly as standards evolve and new vulnerabilities emerge. This concept is called crypto-agility.

Cryptographic agility (crypto-agility) is the organisational capability to systematically manage cryptographic assets, and to modify, replace, or upgrade any component of the cryptographic stack in a controlled and coordinated manner, across all systems and dependencies, without causing operational disruption.

Stop hard-coding your cryptographic libraries. Monolithic security is dead. The core of your defence strategy is crypto-agility: the ability to swap out cryptographic algorithms without tearing your entire pipeline apart.

As noted in the IEEE Computer Society's analysis, we're currently in a "hybrid" phase — security teams are layering quantum-resistant models on top of classical systems.

This hybrid approach lets you maintain compliance with current standards while you build quantum-resistant defences. Use it as a bridge, not a permanent solution.

Practical Tips: What IT Teams Should Do Right Now

You don't need to wait for a full quantum threat to materialise before acting. Here's a prioritised action plan that your team can begin executing immediately:

1. Conduct a Cryptographic Inventory (CBOM)

Quantum readiness requires knowing where cryptography is used, identifying systems and data most exposed to quantum risk, and building a practical migration plan for quantum-resistant algorithms.

Build a Cryptographic Bill of Materials — catalogue every application, API, library, certificate, VPN, and protocol that uses RSA or ECC.

2. Classify Your Data by Sensitivity and Longevity
Not all data carries the same risk.

Data with long confidentiality requirements is already at risk. If information must remain secure for 10, 15, or 25 years, it is vulnerable today. The fact that it cannot yet be decrypted does not reduce the danger of it being collected and stored.

Prioritise protecting long-lived sensitive data first.

3. Adopt a Hybrid Encryption Approach Now

Use a "hybrid mode" — combine your classical encryption with PQC. You keep your current compliance while gaining that critical, future-proof layer of defence.

This is low-risk and implementable today using existing TLS library support such as OpenSSL 3.2+.

4. Update TLS and VPN Infrastructure

The IETF TLS working group is standardising hybrid ML-KEM key exchange, with browser and CDN implementations already in production. Enterprise deployment requires TLS library support (OpenSSL 3.2+ or BoringSSL) and server-side configuration. It is a configuration project, not a hardware replacement.

5. Train Your Team and Align Vendors

Train your team regularly with workshops or certifications to keep their PQC skills sharp, and build crypto-agility into your systems so you can swap algorithms fast if new threats or standards emerge.

Equally, begin vendor conversations now — ask suppliers to confirm their PQC roadmaps and timelines.

6. Establish a PQC Migration Governance Structure

Before implementing technical changes, establish a governance framework by setting up a dedicated PQC migration team that includes stakeholders from various use cases. This team should own the roadmap, assign responsibilities, monitor progress, and align PQC goals with your organisation's long-term strategy.

7. Stay Current on Evolving Standards

Keep tabs on quantum computing and cryptanalytic developments through industry reports, conferences, or threat intelligence feeds to stay ahead.

NIST continues to evaluate additional backup algorithms, and the landscape will continue to evolve.

Conclusion: The Time to Act Is Now

The quantum threat to encryption is not a headline from the future — it is a strategic risk your organisation is already exposed to today.

The U.S. government, through NIST and CISA, has agreed the threat is real and has issued several cybersecurity resilience mandates. The industry is aligned on the danger and understands that because the migration takes years, the time to start is now.

Organisations will invest heavily in data protection programmes, mapping encryption and preparing for migration to quantum-safe algorithms. Those that integrate quantum readiness into overall risk management in 2026 will be best positioned to adapt as breakthroughs accelerate.

The organisations that move earliest will have the smoothest migrations, the lowest costs, and the most defensible security postures. Those that delay will face rushed, expensive transitions — or worse, find themselves holding data that has already been quietly collected by adversaries just waiting for the right quantum moment.

Ready to begin your quantum-resistant encryption journey? Start by conducting a cryptographic inventory of your systems this month, identify your highest-risk data assets, and begin evaluating hybrid PQC deployment options with your security team. The NIST standards are finalised, the tools are available, and the clock is running — make sure your organisation is ahead of it.