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Quantum computers are expected to supply the most powerful computing capabilities ever. Advances in quantum computing are finally beginning to reach commercial applications, such as IBM’s Q System One, the world’s first quantum computing system designed for commercial use, or Google’s claimed “quantum supremacy” when its computer successfully completed a task in 200 seconds that would have taken a traditional computer thousands of years to complete.
But quantum computers could also undermine the cryptographic defenses of data and electronic communications such as in e-commerce sites, emails, credit bank accounts, etc. Quantum computers aren’t powerful enough to do this today. A US National Academies study says that to pose a real threat, quantum machines will need far more processing power than today’s best quantum machines have achieved. However, it is possible that in a little more than a decade — and perhaps even sooner — these machines could be a threat to widely used cryptography methods.
That’s why researchers and security firms are racing to develop new approaches to cryptography that will be able to withstand future quantum attacks mounted by hackers.
There are two main types of encryption. Symmetric encryption requires a sender and a receiver to have identical digital keys to encrypt and decrypt data, whereas asymmetric — or public-key — encryption uses a publicly available key to let people encrypt messages for a recipient who is the sole holder of the private key needed to unscramble them. Sometimes these two approaches are used together.
The goal is to stop hackers from using massive amounts of computing power to try to guess the keys being used.
However, quantum computers could help hackers work their way back much faster through algorithmic trapdoors – mathematical constructs that are relatively easy to compute in one direction to create keys, but are very hard for an adversary to reverse-engineer. Unlike classical computers, which use bits that can be either 1s or 0s, quantum machines use qubits that can represent numerous possible states of 1 and 0 at the same time—a phenomenon known as superposition. They can also influence one another at a distance, thanks to a phenomenon known as entanglement.
Thanks to these phenomena, adding just a few extra qubits can lead to exponential leaps in processing power.
According to technologyreview.com, it is highly unlikely that quantum computers breach cryptographic defenses soon, still, “Y2Q” — the year in which quantum code-cracking becomes a major headache — may arrive faster than we think.
New kinds of cryptographic approaches that can be implemented using today’s classical computers but will be impervious to attacks from tomorrow’s quantum ones are called post-quantum cryptography. The aim is to zero in on one or a few methods that can be widely adopted. The US National Institute of Standards and Technology launched a process in 2016 to develop standards for post-quantum encryption for government use.
Interested in learning more about quantum applications? Attend i-HLS’ InnoTech Expo in Tel Aviv – Israel’s largest innovation, HLS, and cyber technologies expo – on November 18-19, 2020 at Expo Tel Aviv, Pavilion 2.