We are used to logging in, paying online, or sending messages without thinking much about what keeps that data secure. Today, the safety of those everyday actions depends on encryption: mathematical algorithms that make information unreadable to anyone who doesn’t have permission. Those techniques are currently considered safe because breaking them would take a normal computer far too long to be practical. But that foundation is expected to change.
A different kind of computer
Companies like IBM and Google are trying to develop quantum computing processors: chips that work according to the rules of quantum physics rather than traditional binary logic. Once they reach sufficient capability, they will be able to crack many of the encryption systems that protect the modern internet. “That is no longer a hypothetical question,” says Ginevra Fabrizio, PhD researcher at UT. “The issue isn’t if this will happen, but when.” And although quantum computers can’t break today’s encryption yet, attackers can already store encrypted data now and decrypt it years later when better technology becomes available. This kind of attack is referred to as Harvest Now, Decrypt Later.
New encryption methods
To stay ahead, researchers are developing post-quantum cryptography: new encryption methods designed to remain secure even against quantum computers. These newer methods often require more computing power. What is now an invisible, almost instant security check between two devices may take noticeably longer with our current computing power. “That matters,” Ginevra explains. “A small delay multiplied across millions of connections can disrupt services we rely on.” This is why companies like Apple, Google and Signal are already deploying hybrid algorithms that combine current encryption standards with post-quantum ones. Meanwhile, organisations such as NIST (in the USA) are trying to standardise these new post-quantum algorithms, allowing a gradual transition.
Studying how this works in the real world
Ginevra’s research focuses on how these new methods behave when used across everyday networks, not just in controlled lab conditions. Working with real network traffic data provided by company providers, she examines performance under realistic internet use: busy periods, multiple services running at once, and varied connection speeds. “Having real data lets us see where the slowdowns actually appear,” she says. “It gives organisations something concrete to work with when planning when and how to make the transition.”
Adapting the internet to post-quantum cryptography won’t be a simple software update. It affects everything from cloud platforms to banking systems, from university networks to personal devices at home. Even routers and small “smart” appliances rely on encrypted communication in the background. “The internet is enormous, distributed and interconnected,” Ginevra says. “Changing the way it stays secure is a long, gradual process. But the earlier we start, the smoother that transition will be.”
