Quantum Computing Threat to Cybersecurity

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There is an epic battle happening right now between two technologies. The first is a classical computing technology that has been around for about 70 years and is currently the most powerful and useful of the two. While classical computing has improved by leaps and bounds over the years, further advancement is getting more difficult as it pushes the limits of physics. The second is a quantum computing technology that has been around for about 20 years. Quantum computing’s potential is so great and the technology is so new. We have only scratched the surface of what can be done with the technology, and it’s only a matter of time until a quantum computer will be able to be the best supercomputer at solving a problem.


Quantum Computers are devices that perform quantum information processing using the physical reality that quantum theory tells us about for the purposes of performing tasks that were previously thought impossible or infeasible.
Quantum supremacy is when a quantum computer is able to perform a task a conventional computer can’t do.
Qubits are a unit of information that quantum computers use to perform tasks.
Symmetric algorithm can also be called a secret key algorithm, which uses only one key, a secret key for encryption and decryption of messages.
Asymmetric algorithm can also be called public-key cryptography, which uses private and public keys to encrypt and decrypt the data. 

Classical Computers Vs Quantum Computers

Classical computers use bits, and their operations are based on one of two positions. A single state, such as on or off, 1 or 0, is called a bit. Quantum computers use qubits, which can be either or both simultaneously. This quantum phenomenon is known as superposition, and that gives it massively greater processing speeds.

So, take two bits from a classical computer. Those bits can be in four possible states, 00, 01, 10, or 11, and classical computers need to stack incredible amounts of bits to improve their processing power. The best supercomputers today have hundreds of trillions of bits, but with a quantum computer, the basic unit of information is a quantum bit, or qubit. Two qubits can represent the same four states of 00, 01, 10, or 11, but they can also represent all four states at the same time.

Qubits are highly susceptible to disturbances by their environ­ment, which makes both qubits and qubit op­erations (the so-called quantum gates) ex­tremely prone to error.

Big Players in Quantum Computing

There are various players working on and innovating quantum computing, despite quantum computers still being in their infancy stage. Some of the big tech companies, institutes, and startups are running the race for quantum supremacy.

Google Quantum AI Lab

Google AI Quantum is advancing quantum computing by developing quantum processors and novel quantum algorithms to help researchers and developers solve near-term problems both theoretical and practical. The company thinks quantum computing will help it develop the innovations of tomorrow, including AI. That’s why it is committed to building dedicated quantum hardware and software today. Quantum computing is a new paradigm that will play a big role in accelerating tasks for AI. It offers researchers and developers access to open source frameworks and computing power that can operate beyond classical capabilities. Google is aiming to build a “useful, error-corrected quantum computer” by the end of the decade. the company explained in a blog post.


IBM Quantum is the trusted partner to help you start your quantum journey and prepare for the era of quantum advantage. You can discover early use cases, equip your organization with practical quantum skills, and access world-class expertise and technology to advance the field of quantum computing. It is your most passionate collaborator to advance foundational quantum computing research that will make a real-world impact. Work with the best experts across experimentation, theory, and computer science and explore new possibilities in the field of quantum computing.


Microsoft takes a comprehensive approach to deliver all the technology needed to enable commercial impact with quantum encompassing everything from development to deployment. This approach innovates in parallel at all layers of the computing stack, including controls, software, and development tools and services. It also includes a major ongoing focus to develop the topological qubit to help make scalable, stable quantum computing a reality.

 Rigetti Computing

The Rigetti computers are expected to be available in the first quarter of 2022. The company says it will be the largest quantum computer accessible on the internet Azure Quantum. Rigetti quantum computers use superconducting qubits, which it claims have faster execution times and greater scaling than other commercially available quantum computing technologies.

Applications of Quantum Computing

The theoretical potential of quantum computers is significant and wide-ranging. Many fields could benefit from the computational advantages of solving problems in a completely different way compared to classical computers. Below are some of the applications of quantum computers.

  • Cybersecurity
  • Artificial Intelligence
  • Traffic Optimization
  • Drug Development
  • Electronic Materials Discovery
  • Financial Modelling
  • Better Batteries
  • Weather Forecasting and Climate Change

Quantum Threats to Cybersecurity and Post-Quantum Cryptography

The arrival of quantum computing will result in adjustments to encryption strategies. presently, the most widely used asymmetric algorithms are primarily based on hard mathematical problems, including factoring large numbers, that can take lots of years on today’s most effective supercomputers.

However, research performed by Peter Shor at MIT more than two decades in the past demonstrated the equal problem should theoretically be solved in days or hours on a large-scale quantum computer. Future quantum computers may have the ability to break asymmetric encryption solutions that base their security on integer factorization or discrete logarithms.

Even though symmetric algorithms are not affected by Shor’s algorithm, the power of quantum computing, the latter necessitates a multiplication in key sizes. For instance, big quantum computers running Grover’s algorithm, which use quantum standards to look at databases in no time, ought to offer a quadratic development in brute-force attacks on symmetric encryption algorithms, like AES.

To help withstand brute-force attacks, key sizes need to be doubled to provide the same level of protection. For AES, this means the use of 256-bit keys to preserving today’s 128-bit security strength.


Quantum computers will be incredibly powerful and will have the potential to provide tremendous societal benefits. However, there are threats related to how quantum computers could be used by our adversaries, competitors, or criminals. For example, a malicious entity can capture communications of interest these days. Then, when quantum computers are available, that substantial computing power could be used to break the encryption and find out about those communications.

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M.I Kani
M.I Kani

Mahmoud is a web3 developer and security researcher. His expertise includes blockchain and cybersecurity. The topics he writes about include blockchain, metaverse, web3, cyber threats, and security defenses, as well as research and innovation in information security.

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