By Rob O’Connor
Quantum computing has long been seen as a distant concept – complex, hypothetical, and always ten years away. But the situation is changing. The tech giants are making tangible progress in stabilising and scaling quantum systems, moving the technology from theoretical to practical. However, while this shift has huge potential to transform many sectors, it also has unprecedented implications for the world of cyber security.
Once quantum computing becomes viable at scale, much of today’s encryption – the backbone of secure communication, transactions, and data storage – will be rendered obsolete. This means that the systems that we rely on for privacy and security will need a complete overhaul.
The problem? Most organizations are nowhere near ready. Many underestimate the pace of change, or do not yet grasp how high the stakes truly are. But, as quantum computing moves from research labs to real-world applications, every industry will need to act quickly to protect sensitive data and future-proof critical systems.
The state of quantum computing
Quantum computing always seemed a long way off until, suddenly, it did not. What changed?
One of the fundamental dependencies of this technology is the ability to produce large volumes of stable qubits. Qubits (short for quantum bits) are the building blocks for quantum computing, but unlike classic bits, which are binary (0s or 1s), qubits can exist in multiple states simultaneously thanks to a property called superposition.
This trait gives quantum computers the ability to process enormous amounts of data, allowing them to handle complex problems much faster than traditional computers. But there is a catch: qubits are notoriously fragile and prone to errors. To build a reliable quantum computer, you need to correct those errors – and that takes a lot of qubits!
Despite this complexity, leading companies are making meaningful progress. While we are still in the early stages, the race to produce scalable quantum systems is heating up. It could be commercially viable, at least in certain specialized use cases, even as soon as within the next five years.
This timeline has major implications – especially when it comes to cryptography.
Why current encryption will not survive a quantum computer
Most modern encryption relies on the fact that it takes traditional computers an incredibly long time to break large numbers. Current algorithms like RSA (Rivest-Shamir-Adleman) and ECC (elliptic curve cryptography) depend on this fact to stay secure.
Quantum computers, however, turn this assumption on its head. Using quantum algorithms like Shor’s algorithm, it becomes possible to factor large numbers exponentially faster than classical computers. In practical terms, this means that once quantum machines reach sufficient scale, they could rapidly crack the encryption that protects everything from financial transactions to personal medical data.
In response, the National Institute of Standards and Technology (NIST) and other regulatory bodies are already recommending the adoption of post-quantum cryptography – encryption methods designed to withstand attacks from quantum computers. These include lattice-based cryptography and hash-based signatures. While promising, these approaches often require longer key lengths and more processing power, meaning that businesses will need to update both software and hardware to support them at scale.
The hidden security risks
Unfortunately, however, the threat is not limited to future breaches. One of the most overlooked quantum risks is ‘harvest now, decrypt later’ attacks. In this scenario, a bad actor gains access to encrypted data today, perhaps through a system vulnerability or data breach, and stores it. Currently, the encryption is strong enough to protect the data, but once quantum decryption becomes possible, that same data is likely to become readable.
This is especially dangerous in industries where data has a long shelf life: medical records, government communications, intellectual property, and financial histories. If stolen now and decrypted in the future, the consequences could be dire.
Start preparing today
To stay ahead of the curve, organizations need to approach quantum computing not just as a scientific milestone, but as a business and security imperative. A few immediate steps can help lay the foundation.
First, conduct a comprehensive inventory of where and how encryption is used across your systems, including stored data, data in transit, devices, and vendor services. Understanding your current dependencies is essential for prioritising upgrades.
Second, engage your vendors early. Quantum resilience is not just an internal issue. Organizations need to work closely with their suppliers and partners to make sure that the broader ecosystem, including third-party platforms, is committed to migrating to post-quantum cryptography standards.
Finally, begin exploring quantum-native tools that can strengthen your security posture today. One example is Quantum Random Number Generators (QRNG), which produce truly random numbers by measuring unpredictable behaviours at the quantum level, such as how particles move or change state. Unlike traditional ‘pseudo-random’ number generators, which are based on algorithms and can be reverse-engineered, QRNGs eliminate vulnerability and offer a stronger foundation for encryption.
Quantum readiness is not just a security issue
There is no denying the enormous promise of quantum computing. From solving complex optimisation problems, to accelerating drug discovery, improving AI models, and simulating complicated systems, the possibilities are endless.
But, with this promise comes risk. Organizations that fail to prepare will be exposed – not just from future data breaches, but to reputational damage, operational disruption, and regulatory non-compliance.
The author
Rob O’Connor is EMEA President at Insight
