I was recently in the fortunate position of being asked to provide insights for a global banking client regarding the business values of quantum computers but the most important dimension everyone seems to downplay is the threat to cybersecurity. The digital world has relied on cryptographic algorithms to protect our most sensitive information for decades, but the emergence of quantum computing now represents both an unprecedented opportunity and an existential threat to this security foundation. While many organisations look to NIST to provide the cryptographic standards that will solve this challenge, the reality is that addressing the quantum threat requires a comprehensive layered approach that goes far beyond algorithmic changes alone. At the heart of this crisis lies the Cryptographically Relevant Quantum Computer (CRQC), a theoretical machine capable of executing Shor's Algorithm; a quantum algorithm that efficiently finds the prime factors of large integers by exploiting quantum superposition and interference, to break widely used public-key cryptographic systems like RSA and ECC in seconds.
The Foundation Under Attack
Most modern encryption relies on mathematical problems that are computationally difficult for classical computers to solve. The RSA encryption system depends on the difficulty of factoring large numbers into their prime components, whilst elliptic curve cryptography (ECC) and Diffie-Hellman key exchange protocols derive their security from the discrete logarithm problem. These cryptographic methods form the backbone of internet security, protecting credit card transactions, secure messaging, digital signatures, and classified government communications. However, Shor's Algorithm does not just offer marginal improvement over classical methods, it provides exponential speedup that reduces the time needed to break RSA encryption from millennia to mere hours. Similarly, Grover's Algorithm; a quantum search algorithm that uses amplitude amplification to search unsorted databases quadratically faster than classical methods, provides quadratic speedup for searching unsorted databases, effectively halving the security of symmetric encryption keys.
The Imminent Timeline and "Harvest Now, Decrypt Later"
Recent developments have dramatically accelerated the quantum threat timeline. Google researcher Craig Gidney's 2025 research shows that breaking 2048-bit RSA encryption could require 20 times fewer quantum resources than previously estimated, just one million noisy qubits operating for one week, compared to earlier estimates of 20 million qubits. NIST's current guidance recommends retiring vulnerable systems after 2030 and prohibiting them altogether after 2035, making the transition to quantum-safe cryptography increasingly urgent.
The threat is not merely future-focused. Adversaries are already engaging in "harvest now, decrypt later" strategies, intercepting encrypted data today with the intent to decrypt it once quantum capabilities mature. This poses grave risks to long-lived sensitive data such as financial records, health information, and government communications.
Migration Complexity: The Cryptographic Lag Challenge
Transitioning to quantum-safe cryptography is not a simple upgrade. Legacy systems are often hardwired to specific cryptographic standards, and migrating to post-quantum algorithms requires deep architectural changes. These modifications are difficult to implement without downtime or performance degradation, an unacceptable risk in high-availability environments like banking and finance. The journey to quantum readiness could take a decade or more, requiring global collaboration and careful planning. The longer organisations delay migration, the more vulnerable they become to quantum-enabled breaches.
IOWN: Photonics as the Solution
The IOWN (Innovative Optical and Wireless Network) initiative offers a promising path forward through photonics technology. IOWN leverages All-Photonics Networks (APN) to deliver ultra-high-capacity, low-latency communication infrastructure, particularly valuable for secure financial services platforms where speed and integrity are paramount.
Photonics-based systems process information using light rather than electrical signals, offering several advantages: dramatically reduced latency, lower power consumption, and enhanced security through optical processing that is more difficult for quantum computers to compromise. The network's cognitive capabilities enable dynamic adaptation to emerging threats and automatic implementation of quantum-safe protocols.
Quantum Key Distribution: Unbreakable Key Exchange
QKD represents one of the most promising defences against the quantum threat. This technology leverages fundamental principles of quantum mechanics to create theoretically unbreakable key distribution, relying on quantum properties such as superposition and the no-cloning theorem to detect any attempt at eavesdropping.
In QKD systems, encryption keys are transmitted using quantum states of photons. If an attacker attempts to intercept these quantum states, the act of measurement necessarily disturbs them, alerting legitimate parties to the security breach. This provides information-theoretic security rather than computational security, remaining secure regardless of the attacker's computational power.
Post-Quantum Cryptography: Algorithmic Resilience
Whilst photonics enhances transmission security, post-quantum cryptography (PQC) focuses on algorithmic resilience. PQC algorithms are designed to withstand quantum attacks by relying on mathematical problems that remain hard even for quantum computers, such as lattice-based, hash-based, and multivariate polynomial equations. The synergy between photonics and PQC is powerful. Photonics ensures secure key exchange and transmission, whilst PQC secures the data itself. Together, they form a robust defence against quantum-enabled threats, incorporating NIST-approved post-quantum cryptographic algorithms for comprehensive protection.
Strategic Enterprise Action
Major organisations are actively exploring quantum-secure propositions, including QKD testbeds and cryptographic agility frameworks. These initiatives represent strategic shifts in how enterprises approach cybersecurity in the quantum era, focusing on practical solutions that allow seamless switching between algorithms. The quantum revolution is inevitable, but with technologies like QKD and architectures like IOWN, we can build a secure digital future that harnesses quantum computing's benefits whilst defending against its threats through quantum-resilient systems.
