There has been a growing interest in quantum computing in recent years, and along with it an increased focus on developing cybersecurity to protect against the accompanying quantum threats that could have widespread impact on our society’s critical infrastructure.

Current encryption will not remain secure indefinitely. Preparing for such a time when traditional cryptography becomes obsolete necessitates an understanding of the encryption methods that will replace it. So what exactly is post-quantum cryptography, and how does it differentiate from quantum encryption?

Post-Quantum Cryptography vs. Quantum Encryption — Explained

First, in order to better understand the difference between post-quantum cryptography and quantum encryption — a bit of a history lesson.

In 1994, an American mathematician named Peter Shor developed what’s known as Shor’s Algorithm, a quantum computer algorithm that when used with a then entirely theoretical quantum computer could solve mathematical problems in ways a classical computer never could, in exponentially less time.

Now that working quantum computers are actually being built, it is but a matter of time before a quantum computer arrives with enough qubits to break current RSA encryption.

This level of certainty around the end of RSA encryption has encouraged research into ways to make sure our information remains secure into the future.

That’s where post-quantum cryptography and quantum encryption come into play.

Post-Quantum Cryptography

Post-quantum cryptography (also known as quantum-proof, quantum-resistant, or quantum-safe) is based on mathematical problems, just like traditional cryptography, but those math problems are exponentially more difficult to solve, making them able to withstand cyberattacks from quantum computers running Shor’s algorithm, where traditional cryptography would fail. Post-quantum cryptography does not use any quantum properties, nor rely on any specialized quantum hardware.

In 2016, the National Institute for Standards and Technology (NIST) introduced a competition for post-quantum cryptography standardization with the goal of finding the strongest quantum-resistant public-key encryption algorithms which could replace the three current standards most vulnerable to quantum attacks. In July of 2022, they announced four selected algorithms, from which a standard for all post-quantum cryptography will be set — the next step toward post-quantum cryptography becoming more widely adopted by businesses and governments.

Quantum Encryption

Unlike post-quantum cryptography, quantum encryption (or quantum cryptography) is based on physics, relying on the properties of quantum mechanics and leveraging the unpredictable nature of matter at the quantum level for securing communications.

Rather than encoding information in bits, quantum encryption uses quantum bits, or qubits, just as a quantum computer would — in a sense, defending against quantum with quantum.

Because quantum encryption relies on the laws of physics rather than mathematical problems, it can remain secure regardless of computing power.

The best example of quantum encryption is quantum key distribution (QKD), which makes it possible to transmit information while making eavesdropping impossible without detection. A secret, random key is transmitted through a series of photons. If someone attempts to “listen in” on the transmission, the photons are disrupted, changing the outcome on each end, a law in quantum mechanics known as the uncertainty principle.

QKD has not been widely used due to technological limitations that have made it impractical at enterprise scale — dedicated hardware is required, including fiber optic cables to send and receive data.

Fortunately, there are digital alternatives being developed by data security companies to solve for these impracticalities, retaining the significant security benefits of QKD while making it easier to implement, and a much more viable option at enterprise scale.

The transition away from current encryption is inevitable, and while it can seem daunting, understanding post-quantum cryptography and quantum encryption is an important first step organizations can take toward readiness. The next step will be taking stock of current cryptography in use, and planning for solutions that can protect information against this very real quantum threat.

Quantum-Resistant, Game-Changing Data Security

Better data security solutions to protect against impending quantum compute threats are available now.

Theon Technology employs an advanced mathematical equation to propagate truly random cryptographic keys at scale leveraging proprietary software. Our software utilizes patented algorithms to deliver on the promise of a truly scalable, commercially viable, enterprise ready, One Time Pad without the need for specialized hardware.

Theon’s Random Number Generator (RNG) Archimedes generates high-entropy keys at scale with speed and economy, designed to frustrate the twin challenges of mathematical advances and quantum processing power. And because Archimedes is software-based, computing hardware and processing power required to support key generation can be adjusted as needed, unlike hardware-based RNGs that require greater power and physical resources to support effective cryptography.

Theon’s Hypatia harnesses the power of the unbeatable cryptographic standard, the One Time Pad. Solving for the problem of large and unwieldy OTP files, Hypatia reduces the bandwidth required to support OTP key transmission, making it feasible across more use cases.

Theon Technology sets a new standard for software-based cryptography. While also being a recognizable successor, it represents a paradigm shift in data encryption, and a next-generation game-changing solution for organizations.


Revolutionize your data security for the quantum age — Reach out to a Theon expert today to find out how. We also have free eBooks available for download, including Cryptography’s End, which preps you with an understanding of the end of cryptography as we know it and why quantum-proof encryption is so critical to the future of cybersecurity.