Post-Quantum Security

Quantum Computers and the Q-Day

Quantum computers are specially designed computers that can utilise quantum mechanisms to perform calculations that revolutionise computation for specific tasks. They operate on fundamentally different principles compared to classical computers. Due to their high capability, they are expected to solve certain problems exponentially faster than traditional machines.

One famous example is Shor’s Algorithm, developed by Peter Shor in 1994. It can factor large numbers in polynomial time, something that would break RSA, ECC (Elliptic Curve Cryptography), and Diffie-Hellman protocols, which together secure over 90% of today’s digital world (Chen et al., 2016).

However, for the same reason, quantum computers also pose a significant risk as they can be utilised to attack traditional cryptographic schemes currently in use. This would compromise the confidentiality and integrity of digital communications.

As quantum computing inches closer to practicality, the digital systems that protect global banking, military communications, healthcare systems, and even everyday messaging applications face an unprecedented threat. This event is commonly referred to as Q-Day. Preparing for this day is not optional but essential.