The success of the modern digital economy depends on encryption. Without it, digital services such as ecommerce platforms, collaboration apps, messaging tool and software-as-a-service would be rendered practically useless. Private messages, payment data and sensitive information of all sorts would bleed out from their intended channels, threatening the privacy and security of essentially every internet user.
Encryption, the process of securing data and internet traffic, is a cornerstone of the connected world. But experts warn that quantum technology could one day cause these traditional privacy protections to crumble – and security pros are calling that impending event ‘Q-day’.
What is Q-day and why does it matter?
Traditional computing runs on binary ‘bits’ of information, where each unit can be coded as either 0 or 1. Quantum computing, however, uses so-called qubits, or quantum bits, which can occupy both 0 and 1 positions at the same time. This ability to hold seemingly conflicting information simultaneously is known as superposition, and it’s similar in this way to the human brain, which can hold contradictory thoughts.
Although quantum computers already exist, they are unwieldy and only useful for specialised tasks, such as solving complicated mathematical equations. However, once the machines are stable or commercially available, their ability to make such calculations, through methods such as Shor’s algorithm, might put encryption at risk.
Encryption relies on factoring extremely large numbers, which is difficult for even the most powerful classical computers. Quantum computers will one day be able to solve such equations easily, thereby ‘breaking’ encryption codes.
While quantum computers are not yet powerful or stable enough to crack these codes, and likely won’t be for decades, their potential has security professionals worried. And, with quantum researchers at Google and IBM working diligently to progress the technology, Q-day might come quicker than we’d previously assumed.
Q-day: the security implications of quantum computing
Countries were quietly investing in quantum computing long before generative AI captured the headlines. The Chinese government has ploughed significant resources into quantum initiatives, hoping to become a leader in the field. It already publishes more research papers on quantum computing than the US, its biggest rival and the current leader in the field. Meanwhile, the UK has just switched on a new machine, described by the BBC as the “most advanced in the world”, in Oxfordshire at the National Quantum Computing Centre.
Private sector businesses readily share their progress on quantum computing. But experts worry government-backed labs could develop a stable, powerful quantum computer and not share the news with anyone. Such a machine would enable its owner to decipher any encrypted communications on the planet. No wonder then that they’d choose to keep their breakthrough a secret.
Cybercriminals are preparing for Q-day, too. Many have implemented a ‘harvest now, decrypt later’ strategy, meaning they steal as much data as possible – even encrypted data that they can’t currently access – with the hope that they will be able to decrypt it later.
In response, so-called quantum-readiness initiatives are gaining momentum. Encryption labs are developing post-quantum cryptography methods, which are designed to be unsolvable even by powerful quantum machines.
While Q-day may still be years away – and some argue that it will never arrive; it’s a myth, drummed up by quantum companies to build hype – firms would do well nonetheless to investigate their cryptographic capabilities with up-to-date risk assessments, ensuring that internet traffic and data is as secure as possible and ready for whatever the future holds.
The success of the modern digital economy depends on encryption. Without it, digital services such as ecommerce platforms, collaboration apps, messaging tool and software-as-a-service would be rendered practically useless. Private messages, payment data and sensitive information of all sorts would bleed out from their intended channels, threatening the privacy and security of essentially every internet user.
Encryption, the process of securing data and internet traffic, is a cornerstone of the connected world. But experts warn that quantum technology could one day cause these traditional privacy protections to crumble – and security pros are calling that impending event 'Q-day'.
