CONVENTIONAL COMPUTERS WORK using traditional electronic signals, forced into two states called bits and represented by 0 or 1. Computers link these bits together to create numbers. These numbers can be huge, and manipulating these numbers to achieve a goal usually happens very quickly. Currently, an upper performance limit exists for even the most powerful supercomputers.

This performance limitation is, in some ways, fundamental to current Internet security. This means that it is computationally impossible to crack the current cryptographic algorithms that are used to protect data and transactions. This helps protect the security and integrity of a wide range of documents, such as highly classified government data and electronically signed business documents. But the computational and mathematical assumptions on which much of today’s cryptographic security is based are getting closer and closer to being disrupted by quantum computing.

Governments and private entities are investing billions to harness this “revolutionary” computing power, based on physical quantum phenomena. Quantum computers can easily handle complex, data-intensive tasks, such as facilitating the development of life-saving drugs, simulating complex financial markets, or predicting the weather more accurately. In addition to unleashing these positive applications, quantum computers can disrupt the security infrastructure of the Internet because they are not constrained by the computational limits of traditional computers. As a result, they pose a threat to public-key encryption, which ensures the security and integrity of much of today’s digital interactions.

“Quantum computing promises great potential. Today, so many individuals and organizations rely on public-key cryptographic algorithms to secure sensitive data and communications, we all need to consider the impact on the security and privacy of communications. and computations with the emergence of quantum technologies,” said Deborah Golden, US Head of Cyber ​​and Strategic Risk for Deloitte Risk & Financial Advisory and Director at Deloitte & LLP key. “Organizations should start taking steps to understand how they leverage cryptography in their operations and what encrypted data and services may be subsequently vulnerable as quantum computing expands. Quantum cybersecurity can open up more robust and compelling opportunities for the security of critical and sensitive data.

Assessing the Quantum Threat

The threat of quantum computing to some public-key cryptography algorithms comes from its ability to decompose large numbers into their prime factors with incredible speed. Instead of relying on simple binary bits, they rely on physical quantum phenomena, such as superposition, which means a particle can be in multiple states at once until it is measured. Quantum scientists use these properties to create quantum bits, or qubits, that can represent multiple numbers at the same time, rather than calculating them one by one as conventional machines do.

Yet it is difficult to get quantum computers to perform these calculations, according to Colin Soutar, managing director of Deloitte Risk & Financial Advisory, Deloitte & LLP key. They need many qubits to perform calculations and to support error corrections that improve the reliability of this delicate technology. These qubits are difficult to create and tangle.

However, technology is changing rapidly and on many fronts. As scientists work to increase the number of qubits, mathematicians are finding new algorithms that have already reduced the needed number of qubits by orders of magnitude. Estimates of how long it would take for the quantum to threaten current cryptographic algorithms vary.

“Regardless of how long it will take to bring IT to market