Introduction
For decades, our digital world has relied on cryptographic systems like RSA and ECC to secure communications, authenticate users, and protect sensitive data. These classical algorithms have proven remarkably robust, but a new kind of computing power is emerging that could change that.
Quantum computing, once a theoretical concept, is steadily moving toward practical reality. While no one can predict the exact moment when a quantum computer will be able to break today’s encryption, the consensus across governments and industry is clear: we need to prepare now for a post-quantum world.
The Quantum Threat: Real but Gradual
A sufficiently powerful quantum computer could render much of today’s public-key cryptography obsolete, exposing everything from banking transactions to state secrets. But even though such machines don’t yet exist, the risk isn’t only about the future.
Attackers today can “harvest now and decrypt later”, by stealing encrypted data now with the expectation that they’ll be able to unlock it once quantum capabilities arrive. For organizations handling sensitive or long-lived data, this creates an immediate security concern.
The primary risk is for the key exchange part of protocols like TLS 1.3: if an attacker captures a full handshake (with the key agreement material) today, they could decrypt that data in the future once the key-agreement primitive is broken.
By contrast, the digital signatures used for authentication in TLS must be verified in real time during the handshake; they cannot be retroactively forged once the session is over. Therefore, the risk for signatures is different: classical signature schemes (e.g., RSA, ECDSA) will become vulnerable when quantum computers appear, but that vulnerability applies to new signature generations (e.g., new certificates or new signed messages) rather than to past sessions that already completed successfully.
Timelines vary; some experts say we might have a capable quantum computer in 10–20 years, others suggest breakthroughs could accelerate that timeline. Either way, transitioning global cryptographic infrastructure takes years of planning, testing, and coordination. Waiting until quantum machines arrive would be far too late.
The State of Post-Quantum Cryptography
In response, researchers and standards bodies have spent years developing and testing new algorithms designed to resist quantum attacks.
The U.S. National Institute of Standards and Technology (NIST) has already selected a set of algorithms for standardization (Kyber for key encapsulation and Dilithium for digital signatures), while organizations such as ETSI, ISO, and the IETF are working to integrate PQC into existing protocols and frameworks.
At the same time, technology vendors are starting to add hybrid cryptographic solutions, which combine classical and quantum-resistant algorithms (for example hybrid KEMs inside TLS). This helps ensure interoperability and a smoother migration path as the standards mature.
In short, the ecosystem is evolving rapidly, but it’s not yet plug-and-play. Adoption will require planning, testing, and coordination across software, hardware, and compliance systems.
Here is a snapshot of current browser support for post-quantum key exchange (hybrid classical + PQC) in TLS/HTTPS environments:
| Browser |
PQC Key Exchange Status |
| Google Chrome (desktop) |
Supported and enabled by default (for desktop) |
| Mozilla Firefox |
Supported (may require enabling flags) |
| Microsoft Edge |
Chromium-based: inherits Chrome support |
| Apple Safari (macOS/iOS) |
Lagging |
How Urgent Is Migration?
The urgency depends on what kind of data you protect and how long it must remain secure.
- High urgency: For government, defense, healthcare, finance, and critical infrastructure organizations, the time to act is now. Any data that must remain confidential for a decade or more is already at risk.
- Strategic urgency: For all others, the key is to start preparing. Understanding your cryptographic landscape and building flexibility into your systems today will save enormous time and cost tomorrow.
What Organizations Should Do Now
You don’t need a quantum computer to start getting ready for one. Here are the essential first steps:
1. Assess and inventory your cryptography
Map out where encryption and digital signatures are used across your organization, from TLS connections to IoT devices to cloud workloads. Document key lengths, certificate usage/expiry, dependencies (hardware, firmware, libraries) and understand the “lifetime” of the data you protect: how long must it remain confidential, how long must it remain authenticated.
2. Build crypto agility
Design systems that can easily switch algorithms and key sizes without major disruption. This agility will be vital not only for post-quantum migration but also for adapting to future advancements in cryptography.
3. Follow emerging standards and vendor updates
Keep track of developments from NIST, IETF, ENISA, and other bodies. Talk to your technology providers about their PQC readiness and roadmaps.
4. Plan for gradual migration
Begin testing PQC algorithms in non-critical environments. Develop policies for hybrid cryptography, key management, and compliance as standards stabilize.
Conclusion: Readiness Is the Best Defense
Quantum computers capable of breaking today’s encryption may still be years away—but the work required to secure our digital infrastructure against them will take just as long.
Preparing for post-quantum cryptography isn’t about panic; it’s about foresight. The organizations that start building agility and awareness today will be the ones that stay secure when the quantum future finally arrives.