Insights

The intricate giant chandelier of copper tubes, wires, and shielding often leaves people puzzled and curious. This image of a quantum computer is quite striking and unlike any classical computer we've seen before. This unique appearance is not just for show; it's a direct result of the specific technological requirements needed to operate quantum computers, particularly those based on superconducting qubits ...

In the early 1900s, when theoretical physicist Max Planck first introduced the idea of quantized energy levels, he probably didn’t foresee his work eventually leading to machines that could solve problems faster than a caffeine-fueled mathematician on a deadline. Legend has it that Planck embarked on his quantum journey after his professor, Munich University physics professor Philipp von Jolly, discouraged him from studying physics, arguing that "in this field, almost everything is already discovered, and all that remains is to fill a few holes." Thankfully, Planck didn’t listen. A century later, the world is abuzz with quantum computing - a technology and a concept so complex that, for many of us, it’s indistinguishable from magic. From Planck’s quaint beginnings of ...

Sign Today, Forge Tomorrow (STFT) or Trust Now, Forge Later (TNFL) is the digital‑signature equivalent of HNDL. Digital signatures underpin everything from software updates and firmware integrity to identity verification and supply‑chain provenance. Today’s signatures are based on RSA or ECDSA, which quantum computers will also break. When that happens, adversaries won’t just read secrets - they will forge signatures at will. The term Sign-Today-Forge-Tomorrow describes situations where the roots of trust are set at manufacture time and cannot be updated; once quantum computers exist, those signatures become meaningless. Hardware roots such as ePassports, industrial control systems and satellites often embed long‑lived keys; field updates may be impossible or incomplete ...

In quantum computing, the role of logic gates is played by quantum gates – unitary transformations on one or more qubits. These are the elementary “moves” that a quantum computer can perform on quantum data. Just as classical gates compose to implement arbitrary Boolean functions, quantum gates compose to implement arbitrary unitary operations. However, quantum gates have striking differences from classical ones: they are reversible (all quantum gates correspond to invertible unitary matrices), they can create superposition and entanglement, and there are infinitely many possible single-qubit gates (since a qubit’s state is a continuous point on the Bloch sphere) ...

Every CISO understands the simple truth: you can’t protect what you don’t know you have. A comprehensive inventory of IT and OT assets - from servers and laptops to industrial controllers and IoT sensors - is the foundation of effective cybersecurity. In theory, building this asset inventory sounds straightforward. In practice, it’s one of the hardest tasks in cybersecurity today. Many enterprises find that even identifying all their IT and OT assets is challenging. In fact, majority of security leaders admit they’ve experienced incidents due to unknown or unmanaged assets. The difficulty only multiplies when you include operational technology (OT) on factory floors and the explosion of Internet of Things (IoT) devices in offices and facilities. Despite investing millions, organizations ...

The Brassard–Høyer–Tapp (BHT) algorithm is a quantum algorithm discovered in 1997 that finds collisions in hash functions faster than classical methods. In cryptography, a collision means finding two different inputs that produce the same hash output, undermining the hash’s collision resistance. The BHT algorithm theoretically reduces the time complexity of finding collisions from the classical birthday-paradox bound of about O(2n/2) (for an n-bit hash) down to O(2n/3) using quantum computation. This represents a significant (though not as dramatic as Grover’s) quantum speedup: for example, a 256-bit hash has ~128-bit collision security classically, but only ~85-bit security under a hypothetical BHT attack ...

Attackers, often employing techniques like model querying, can gather valuable information regarding the target model’s structure, parameters, and learned features, thereby gaining insights into crafting inputs that the model fails to classify correctly. This reconnaissance allows attackers to meticulously modify malicious payloads or network traffic patterns, ensuring that they resemble benign inputs to the model, thus evading detection while maintaining their damaging capabilities ...

Shor’s Algorithm is more than just a theoretical curiosity – it’s a wake-up call for the security community. By understanding its principles and implications, we can appreciate why the cryptographic landscape must evolve. The goal of this guide is to equip you with that understanding, without delving into complex mathematics, so you can make informed decisions about protecting your organization’s data against the quantum threat ...

Quantum Fourier Transform (QFT), like a physical Fourier transform, takes a time-domain wave and represents it in the frequency domain. In the quantum case, the “time-domain” is the computational basis amplitude distribution, and the “frequency-domain” is another basis where the basis states correspond to different phase gradients across the original amplitudes. If the original state has a regular pattern (phase advancing uniformly from one basis state to the next, for instance), then in the Fourier basis it might concentrate entirely on one basis state corresponding to that phase gradient frequency. This is exactly how the QFT finds a period: a state whose amplitudes repeat every r indices will, after QFT, show concentration at multiples of N/r. It’s analogous to how ...

Grover’s algorithm was one of the first demonstrations of quantum advantage on a general problem. It highlighted how quantum phenomena like superposition and interference can be harnessed to outperform classical brute force search. Grover’s is often described as looking for “a needle in a haystack” using quantum mechanics ...

The Hadamard gate takes a qubit and puts it into an equal superposition of “0” and “1” (with a relative phase of + or -). It has a simple matrix but a profound impact: it enables parallelism and interference in quantum algorithms. Historically rooted in Hadamard matrices from mathematics, it has become one of the iconic quantum gates. Whether thought of as a coin flipper, a basis rotator, or a beam-splitter, the Hadamard is an essential tool in the quantum computing toolbox – almost every algorithm uses it. When you see a quantum circuit diagram, those ubiquitous H symbols on lines signal where quantum parallel worlds split and later rejoin to compute what no classical process could do as efficiently ...

In 2010, I was serving as an interim CISO for an investment bank. During that time, I was already trying to figure out the risks posed by quantum computing. One day, I was approached by a vendor who, with great confidence, made two bold claims. First, they insisted that the Q-Day is just around the corner, claiming they had insider information from the NSA suggesting CRQCs were mere weeks away. This, of course, was a load of rubbish. The second claim was even more audacious: they guaranteed that their algorithms were quantum-secure, offering absolute security against any quantum attack. These statements have since become my personal pet peeve as I am increasingly dealing with the quantum risk in my practice ...