Quantum Computing vs. Encryption – A Clash of Technologies 

Published on November 6th, 2023 by Rahul Kumar Singh

Will quantum computers spell the end of modern encryption? As quantum computing harnesses the bizarre properties of subatomic particles to process data in new ways, it threatens to crack the very math securing our digital world. Experts warn that today’s encryption could soon meet its match against the exponential power of quantum.

But while the threat is real, quantum computers are still in their infancy. Cryptographers are racing to shield encryption before this clash of technologies hits. Though an “encryption apocalypse” dominates headlines, quantum-resistant encryption and prudent planning may just save our data in the end.

According to ExpressVPN’s research on encryption’s history, our modern public key infrastructure is potentially vulnerable to the looming quantum threat.

A Brief History of Encryption 

Before diving into the details of quantum computing and encryption, it helps to understand the history of encryption.

Early Ciphers and Cryptography

  • Encryption dates back thousands of years, with simple ciphers used by ancient cultures to protect messages.
  • Cryptography advanced alongside mathematics, with cipher techniques like substitution and transposition becoming more complex.
  • Early encryption was used mainly for military and diplomatic purposes.

The Information Age and Public Key Cryptography

  • The digital revolution increased the need for encryption to protect computer systems and data.
  • In the 1970s, public key cryptography was invented, allowing strangers to communicate securely.
  • Public key systems like RSA and elliptic curve cryptography power ecommerce and secure internet today.

The Quantum Threat Emerges

  • In the 1990s, quantum computing was proposed, with implications for breaking encryption.
  • Shor’s algorithm could theoretically crack RSA and ECC public keys on a large enough quantum computer.
  • Though the threat exists, practical quantum computers are still emerging. Defenses are being developed.

As this history shows, encryption has evolved alongside technology to secure communications. Today’s widespread public key systems could be threatened as quantum matures.

The Power of Quantum Computing

To understand the interaction between quantum computing and encryption, we must explore what gives quantum computing its power.

Qubits and Superposition

  • Quantum computers use qubits instead of binary bits. Qubits can represent 1 and 0 simultaneously via superposition.
  • This allows quantum computers to perform calculations on many states at once in parallel.

Entanglement and Interference

  • Separate qubits can be entangled and act as one unit even when physically apart.
  • Quantum interference from superposition and entanglement creates advantages in computing.

The Promise and Challenges

  • In theory, quantum allows certain problems, like factorization, to be solved much faster.
  • Technical challenges exist in building stable qubits and scaling up systems.
  • If achieved, quantum supremacy over classical computing is possible for some but not all problems.

Quantum introduces fundamental computing advantages, though practical systems are still emerging. This leads to the encryption threat.

Cracking Encryption with Quantum Computers 

Most encryption today relies on mathematical problems that are very difficult for normal computers to solve, like factoring large prime numbers. However, quantum computing changes the game.

Shor’s Algorithm for Factorization

  • Discovered in the 1990s, Shor’s algorithm leverages quantum properties to factor large numbers efficiently.
  • This could be used to break popular public key systems like RSA, threatening security.
  • However, substantial qubits over today’s computers would be needed to run Shor’s algorithm.

Grover’s Algorithm and Symmetric Keys

  • Grover’s algorithm could speed up brute-force attacks against encryption keys.
  • Symmetric systems with keys like AES may be impacted but not necessarily broken.
  • Again, large qubit quantum computers would be needed to see benefits.

When Will the Threat Be Real?

  • Currently, quantum computers are not capable enough to break encryption schemes.
  • Predicting the exact timeline is difficult, but 10-30 years is a common estimate.
  • The threat is real, but encryption is still secure against modern quantum prototypes.

Quantum algorithms like Shor’s and Grover’s pose future risks. But when will quantum computers be ready for such applications?

The Race to Practical Quantum Computing 

To assess the quantum threat, we have to examine the state of quantum computer development:

Major Tech Players and Startups

  • Tech giants like IBM, Google, Intel, and Microsoft are all investing in quantum research.
  • Startups are also entering the space, trying to pioneer quantum technologies.
  • Government labs and academia are pushing theoretical and practical development.

Current Scale and Limitations

  • Right now, quantum computers are limited to less than 100 qubits with high error rates.
  • This small size limits the complexity of problems they can currently solve.
  • Scaling up stable qubits remains a huge engineering challenge.

Timeframes for Cryptanalysis Capabilities

  • Most experts think it will take at least 10 years to develop quantum computers capable of breaking modern encryption.
  • Some predictions put the timeline at 20 years or more from today.
  • Progress is uneven, making timeline predictions difficult. The threat is real but still years away.

Though the pace is accelerating, quantum computers are still quite far from breaking encryption schemes in a practical sense.

Defending Encryption from the Quantum Threat

The good news is that work is already underway to enhance encryption against the risk of future quantum attacks:

Promising Post-Quantum Cryptographic Schemes

  • Cryptographers are developing new public key algorithms resistant to quantum techniques.
  • Leading proposals include lattice-based and multivariate cryptosystems.
  • Work is being done to standardize post-quantum algorithms before quantum matures.

Hybrid Encryption Approaches

  • Current encryption can be strengthened by combining algorithms and keys.
  • For example, double-encrypting communication with both RSA and AES may prevent easy breaking.
  • Splitting data across quantum-resistant and conventional schemes also adds complexity for code breakers.

Managing Cryptographic Agility

  • Encryption methods can be swapped out and upgraded as risks emerge.
  • However, this requires careful planning to scale across users and systems.
  • Cryptographic agility will become more critical as the post-quantum transition approaches.

Researchers are already developing encryption designed to withstand the quantum threat. Deploying these updated schemes in time will be key.

The Path Forward 

Quantum computing and encryption are on a collision course, but the reality is nuanced. While we must take the risks seriously, encryption can adapt to the challenges ahead. Wise preparation now will enable a smooth transition to post-quantum security. With vigilance and continued innovation, our encrypted digital infrastructure can withstand this clash of technologies.

Also read – Top Security Tips for Using Public Networks


The exponential power promised by quantum computing could upend many fields, including the ability to break modern encryption. However, practical quantum computers on this scale are still years away. In the interim, cryptographers are racing to implement quantum-resistant encryption schemes. With prudent planning and upgrades to existing systems, we can defend against this future threat when it finally emerges. The path forward will require agility and foresight to keep our data secure in the coming quantum age.

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Hello friends, I am Rahul, chief editor of HubsAdda. Talking about Tech. I enjoy learning new things related to technology. I love coding 😍

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Lamila Mat
6 months ago

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