All Post-Quantum, PQC Posts
-
Post-Quantum, PQC, Quantum Security
Capability B.3: Below-Threshold Operation & Scaling
“Below-threshold operation” refers to running a quantum processor at error rates below the critical threshold of a quantum error-correcting code. In simple terms, there is a tipping point in error rates: if each quantum gate and qubit has an error probability lower than this threshold, adding more qubits and more error-correction actually reduces the overall error rate of the computation. If error rates are above…
Read More » -
Post-Quantum, PQC, Quantum Security
Capability B.2: Syndrome Extraction (Error Syndrome Measurement)
Quantum syndrome extraction - also called error syndrome measurement - is the process of measuring collective properties of qubits to detect errors without destroying the encoded quantum information. It is essentially the sensor mechanism of a quantum error-correcting code, analogous to measuring parity checks in a classical error-correcting code. In a stabilizer code (the leading framework for quantum error correction, introduced by Gottesman in the…
Read More » -
Post-Quantum, PQC, Quantum Security
Capability B.1: Quantum Error Correction (QEC)
Quantum Error Correction (QEC) is the first and arguably most critical capability in the roadmap toward a cryptographically relevant quantum computer (CRQC). Without QEC, a large-scale quantum computer cannot reliably perform the billions of operations needed to break modern encryption - no matter how many qubits we build. In essence, QEC is what allows many noisy physical qubits to behave like a single near-perfect qubit.…
Read More » -
Post-Quantum, PQC, Quantum Security
Shor’s Algorithm: A Quantum Threat to Modern Cryptography
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.
Read More » -
Post-Quantum, PQC, Quantum Security
Grover’s Algorithm and Its Impact on Cybersecurity
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.
Read More » -
Post-Quantum, PQC, Quantum Security
The Hidden Subgroup Problem (HSP): One Framework to Break Them All
Every public-key cryptosystem deployed today - RSA, Diffie-Hellman, and elliptic curve cryptography - falls to a single mathematical framework called the Hidden Subgroup Problem (HSP). This is not a coincidence: Shor's algorithm, in each of its variants, works by exploiting the Quantum Fourier Transform (QFT) to identify a hidden subgroup inside a finite abelian group. The implication is stark. A cryptanalytically relevant quantum computer (CRQC)…
Read More » -
Post-Quantum, PQC, Quantum Security
Quantum-Safe vs. Quantum-Secure Cryptography
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…
Read More » -
Quantum Computing
Qubits: A Brief Introduction for Cybersecurity Professionals
A qubit is the quantum analog of a classical bit – it’s the basic unit of quantum information. However, unlike a classical bit that can only be 0 or 1 at any given time, a qubit can exist in a combination of both 0 and 1 states simultaneously. This property is called superposition.
Read More »
