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Conventional encryption is dead, say Chinese quantum scientists

Tsinghua University.jpg

The end of current techniques used to encrypt data traffic might be closer than most people think, according to a mathematical paper from China.

A group of 24 scientists say they have devised “a universal quantum algorithm” that may mean data encrypted using today’s technology needs to be encoded with more secure quantum key distribution (QKD).

The White House in Washington has already warned that US Federal agencies need to move to quantum encryption because obsolescent encryption techniques are no longer secure enough.

But this latest paper from China suggests the quantum computer people are more advanced than expected. “To break the widely used RSA-2048 scheme, one needs millions of physical qubits, which is far beyond current technical capabilities,” say the scientists, from Tsinghua University in Beijing (pictured), the State Key Laboratory of Mathematical Engineering and Advanced Computing in Zhengzhou and Chinese institutions.

Instead of needing millions of qubits they demonstrate the use of universal quantum algorithm “by factoring integers up to 48 bits with 10 superconducting qubits”.

The say they have calculated the prime numbers that are factors of the number 261,980,999,226,229, which is a 48-bit number. And they say they need just 372 qubits to factorise a 2,048-bit number.

More work will be needed to test the Chinese scientists’ claim, but quantum computing and encryption specialists, in companies such as Arqit, ColdQuanta, IBM and Toshiba, will be reading the paper carefully and wondering if this is the breakthrough which means the data industry has to switch rapidly to QKD.

The scientists write: “Our study shows great promise in expediting the application of current noisy quantum computers, and paves the way to factor large integers of realistic cryptographic significance.”