Post‑Quantum Cryptography: What It Is and Why It Matters Today

You probably don’t think much about encryption on a daily basis. Most of us don’t. It works quietly in the background, guarding our bank logins, WhatsApp chats, work emails, and everything else we do online. But something is coming that could change the entire game. It’s called quantum computing, and it’s not science fiction anymore.

Over the last few years, some of the world’s biggest tech firms and government labs have been working on building machines that operate differently from the computers we use today. These machines don’t just process faster; they work on an entirely different principle. And if they become powerful enough, they could crack the encryption that protects our digital lives.

That’s where post-quantum cryptography steps in. It’s about creating new ways to protect data; methods that even quantum computers can’t break. To know more about post-quantum cryptography, read on to: 

The Quantum Threat to Modern Encryption

Before you can judge the risk, you must learn how the current encryption works. Currently, a large portion of our digital security relies upon an algorithm referred to as RSA or elliptic curve cryptography (ECC). Both of them are constructed around mathematical problems that are extremely difficult to solve on traditional computers, such as in the case of factoring large numbers or dealing with complicated curves.

Now here’s the issue. Quantum computers don’t follow the same rules. They use something called qubits, which can hold multiple values at the same time. Thanks to this, they can test many possible solutions all at once. It’s like being able to try every key on a giant keyring at the same time rather than one by one.

How Quantum Computing Changes the Game

A classical computer would take hundreds or even thousands of years to break a strong encryption key. But a quantum computer with enough power and the right algorithm, like Shor’s algorithm, could do it in hours or days. That means everything from private messages to classified data could suddenly become vulnerable.

And here’s the catch: even if these machines don’t exist at scale just yet, hackers and rogue groups could be storing encrypted data now, with the intention of unlocking it later. It’s known as a “store now, decrypt later” attack. So even if your information is safe today, it might not be tomorrow.

Impact on RSA and ECC Encryption

Quantum computing poses a direct threat to widely used encryption techniques. A quantum algorithm called Shor’s algorithm can break RSA and ECC by solving the mathematical problems behind them quickly.

This could make current encryption obsolete. Imagine if sensitive data stored today is accessed ten years later by someone using a quantum machine. Even though the data was encrypted when it was stored, it could be unlocked and exposed in the future. This is often called the “harvest now, decrypt later” problem.

What is Post‑Quantum Cryptography?

Post-quantum cryptography, also called quantum-safe cryptography, is a type of digital security meant to resist attacks from quantum computers.

Instead of relying on problems like large number factorisation, which quantum machines can solve quickly, PQC uses different approaches. These methods involve puzzles that remain tough even for future quantum machines.

The best part? These solutions work on regular devices; you don’t need a quantum computer to use them. They’re being built right now by researchers across the world to be both strong and practical.

Types of PQC Algorithms

There isn’t just one method of doing quantum-safe encryption. Researchers are testing multiple techniques. Each one has a different mathematical base but aims for the same goal: long-term security.

Lattice-Based Cryptography

This one’s the frontrunner. It uses something called lattices, which are like grids in high-dimensional space. The math is very complex, and cracking it, even with quantum tech, is considered extremely hard.

Lattice-based systems are efficient and work well across different devices. That’s why many of the most promising PQC algorithms, such as Kyber and Dilithium, are based on this method.

Code-Based and Hash-Based Cryptography

Code-based systems, like the McEliece cryptosystem, have been around for decades. They are based on the difficulty of decoding error-filled messages without the proper key.

Hash-based cryptography relies on mathematical functions called hashes. These methods are particularly strong for digital signatures. An example is SPHINCS+, which is simple but solid.

Each method comes with its own strengths. Some are faster, others are smaller in size, and some are easier to integrate.

Current Standardisation Efforts (NIST PQC Project)

To help industries prepare, the National Institute of Standards and Technology (NIST) in the US began reviewing and selecting post-quantum security algorithms. They aim to standardise the best options so companies around the world can safely adopt them.

In 2022, NIST selected four algorithms: Kyber for key exchange and Dilithium, Falcon, and SPHINCS+ for digital signatures.

These choices are shaping the future of cybersecurity standards, with global adoption expected in the next few years.

Why Now? The Urgency of Post‑Quantum Preparedness

Some people ask, if quantum computers strong enough to break encryption don’t exist yet, why act now?

The answer is simple: change takes time. Updating global communication systems, financial platforms, and national defence networks is a massive task. It’s not like flipping a switch.

Plus, data collected today could still be sensitive in 10 or 20 years. Think health records, financial histories, or government files. If we wait until quantum machines are widely available, we’ll already be too late.

Countries like the US, China, and members of the EU are already investing in quantum defence strategies. Businesses must do the same.

Benefits and Challenges of Post‑Quantum Cryptographic Adoption

Switching to new encryption methods is not as easy as downloading an update. There’s planning involved, and some risks.

What you Gain

• Future-proof security: Your systems will be ready before the threat becomes real.

   

• Stronger trust: Customers know their data is protected long term.

   

• Competitive advantage: Being early shows leadership in digital safety.

   

What Makes it Difficult

• Complexity: Integrating new systems is not plug-and-play.

   

• Compatibility: Older hardware and software may not support these methods.

   

• Cost: Training staff, updating systems, and testing new code can be expensive.

Implementation Challenges in Real-World Systems

Here’s where it gets real. Businesses can’t just swap algorithms like changing a lightbulb. They have to test for:

• Slower performance in older devices

   

• Larger file sizes due to different algorithm structure

   

• Trouble connecting new systems with older servers

All of this requires careful testing, which is why early planning is so important.

Migration Strategies and Planning Ahead

If you’re wondering how to begin, here’s a simple plan:

1. Audit your current infrastructure: Know where your current encryption sits.

    

2. Start with hybrid models: Combine classical and post-quantum algorithms.

    

3. Stay updated:  NIST and other global standards.

    

4. Test gradually: Begin with less critical systems before full deployment.

Security teams should also receive regular training to understand what’s changing and why.

Industry Readiness and Case Studies

Industries that handle sensitive data, like finance, defence, and healthcare, are already moving. Banks are exploring PQC for secure communication. Tech firms are testing browsers that support hybrid encryption. Even cloud services are planning upgrades.

The shift is slow, but the direction is clear.

How Quick Heal Is Embracing Quantum-Safe Cybersecurity

Quick Heal has always prioritised future-ready protection. As quantum tech becomes more relevant, Quick Heal is preparing to integrate post-quantum cyber security across its offerings.

Whether it’s safeguarding individuals through Total Security, protecting multiple platforms with Multi-Device Security, or ensuring business resilience through Antivirus for Server, Quick Heal is committed to adapting before threats become real.

The company’s research and innovation teams are already exploring the best way to roll out quantum-safe features in future updates.

Secure Your Digital Future with Quantum-Safe Solutions

No one can predict the exact moment when quantum machines will go mainstream. But when they do, we won’t get a warning.

That’s why building defences now is the smart thing to do. Post-quantum cryptography is not just about reacting to future tech, it’s about staying ahead of it.

Quick Heal is ready to help individuals and businesses move forward safely. The goal is simple: keep your data secure, not just for today, but for the years ahead.