Quantum computing is no longer science fiction. This revolutionary technology is rapidly advancing from experimental stages and expected to achieve real-world applications in the near future. While quantum computing promises to reshape industries and unlock unprecedented opportunities, it simultaneously introduces serious cybersecurity challenges that could render today’s encryption methods obsolete.

A quantum computer has high computational power, enabling it to solve complex problems at unprecedented speeds. Their ability to crack current encryption methods makes them a significant threat to network security. This situation is extremely serious, which is why organisations like SPTel are spearheading solutions to address post-quantum cryptography issues and implementing protective measures for your data in a post-quantum world.

In this article, we detail why quantum computing is such a significant threat to modern-day cryptographic standards, and explain how businesses can overcome this hurdle through SPTel’s Quantum-Safe Networking solutions.

How Does Modern Cryptography Keep Your Data Safe?

Modern encryption relies on public-key cryptography. Methods like RSA and ECC secure data by creating mathematical problems that are easy to generate but extremely difficult to solve in reverse due to computational complexity. In the modern cybersecurity environment, these systems underpin secure Internet communication, digital signatures, online banking, and more.

RSA

RSA (Rivest–Shamir–Adleman) remains one of the most widely used encryption methods. It uses two extremely large prime numbers to generate a public key and a private key. Multiplying the primes to create a public modulus is easy. However, when factoring the key back into its two original numbers, there are too many potential factors to reliably find the original pair. This method is trustworthy as classical computers struggle to factor very large numbers (e.g., 2048 bits), making brute-force attacks currently infeasible.

ECC

Elliptic Curve Cryptography (ECC) is a more recent, lightweight alternative. Instead of factoring integers, ECC relies on the Elliptic Curve Discrete Logarithm Problem. Given two points on an elliptic curve, computing the multiplier is extremely hard.

Each user has a private number and a public point on the curve. You multiply your private number with a base point to get your public key. Multiplying another user’s public key with your private number gives the same shared secret—but extracting the private number from the public point is computationally impossible for classic computers.

ECC offers equivalent security to RSA with much smaller keys. For example, a 256-bit ECC key matches a 3072-bit RSA key—making operations faster and less resource-intensive.

While these methods are sufficient to securely encrypt our data today, they will not be adequate once quantum computers become widely available. Quantum computers can exponentially outstrip the problem-solving power of modern computers, fundamentally threatening these encryption algorithms. This speed advantage means quantum computers could crack current encryption methods in hours rather than the millions of years required by classical computers, leaving sensitive business data completely vulnerable.

What Can Quantum Computing Accomplish?

Recent experiments demonstrate that quantum computers can tackle enormous problems that classical supercomputers simply cannot, in any reasonable timeframe. Here are some standout examples:

Real-time Simulation of a 127-spin Ising Model

In 2023, IBM successfully ran a real-time simulation of a 2D Ising model—a classic physics problem involving 127 interacting spins, which represents complex magnetic behaviors.

Using error mitigation techniques on their 127-qubit “Eagle” processor, researchers measured how the system’s overall magnetic field evolved over time. This marks the largest quantum spin-system simulation performed to date and a clear demonstration of how quantum processing can handle multi-body physics problems.

Saving 10 Septillion Years of Computational Time

In December 2024, Google unveiled Willow, a 105-qubit quantum processor. In order to demonstrate the capability of quantum computing, Willow performed a standard benchmark computation that was estimated to take today’s fastest supercomputers 10 septillion years to resolve, based on expert estimates.

This astronomical speedup was performed on a modestly-sized quantum chip, showing the sheer multiplicative scale of a quantum computer’s power.

What Does Quantum Computing Mean For Cryptography?

Thanks to the projected ability of large-scale quantum computers to slice through today’s keys in hours or even minutes, modern public-key encryption faces two immediate, strategic threats:

Obsolescence

A computer is estimated to take 300 trillion years to break an RSA-2048 bit encryption key. The reason we have confidence in these encryption methods is that hackers must use an impractical amount of time to brute-force their way through.

However, with the sheer capability of quantum computing, this time-gated cryptography will be a thing of the past. By using Shor’s algorithm, these exponentially complex problems could be broken in 10 seconds, invalidating the entire cryptographic structure.

Harvest Now Decrypt Later

Attackers do not need to wait for quantum computing to advance. By stealing long-lasting data such as banking records, medical history, and other such critical information, hackers can preserve them until the day quantum cryptography becomes accessible enough for misuse. This form of attack is known as ‘Harvest Now, Decrypt Later’. Any data that must remain confidential for years or decades therefore needs quantum-resilient safeguards now, not when the first publicly available quantum computer finally appears.

Find out more about these quantum threats and the risk management measures that CTOs are able to take.

How SPTel Can Defend You Against Quantum Threats Using Quantum-Safe Networking

Understanding how Quantum Key Distribution (QKD) works is essential to appreciating its security benefits. QKD makes use of quantum mechanics to encode secret encryption keys onto single qubits, which are shared between both parties using the encryption method. Any attempt to intercept those photons irreversibly alters their quantum state, alerting SPTel’s trusted nodes and forcing the parties to discard the compromised key. In practice, this means that security is continuously refreshed, creating randomised keys that are immune to HNDL attacks.

Because quantum computing poses such serious threats to current encryption, security standards must adapt and evolve accordingly. SPTel has been actively developing quantum-resistant infrastructure to address these challenges.

SPTel has been trial-running QKD links since 2022 in partnership with local quantum-communications specialist SpeQtral, demonstrating successful quantum-secure connections over our diverse fibre network. Since then, SPTel has been appointed by the Infocomm Media Development Agency (IMDA) to build the National Quantum-Safe Network Plus (NQSN+), Singapore’s first nationwide quantum-safe network.

As an official operator of NQSN+, SPTel has embarked on Quantum Key Distribution (QKD) deployment in three secure nodes across Singapore supported by our diverse island-wide fibre backbone. This Quantum-Safe network for the nation will protect data in transit, whether within or across organisations, against decryption efforts by malicious actors.

SPTel CAN secure your organisation against Quantum threats

• Instant tamper detection – any eavesdropping attempt is detected in real time by SPTel’s Quantum-Safe Network. When tampering happens, the QKD devices will detect the interference. This results in the encryption keys being discarded due to the compromise. The file cannot be decrypted because the key will be discarded, ensuring your data remains secure.
• Future-proof confidentiality – keys generated with QKD provide mathematically proven security that remains unbreakable even against quantum computers, eliminating the need to completely replace security infrastructure when quantum computers mature.
• Seamless deployment – QKD is deployed over SPTel’s diverse fibre pathways with equipment housed within Critical Information Infrastructure. This provides added resiliency through SPTel’s unique fibre pathways and enhanced physical security for the solutions because of our secure edge node locations to house QKD devices.

Preparing for a Quantum Future With SPTel

SPTel’s Quantum Key Distribution (QKD) gives your organisation the capability to proactively protect your data from HNDL attacks, hardening today’s networks against tomorrow’s quantum threats while there’s still time to plan. Starting your quantum-safe journey early is crucial—organisations that begin planning and implementing quantum-resistant solutions now will be better positioned to maintain data security when quantum threats become reality. Delaying these preparations could leave your critical information vulnerable during the transition period.

Ready to safeguard your business in Singapore’s quantum future? Explore how SPTel’s Quantum-Safe Network services can be integrated into your infrastructure today, or contact our team to find out more.