“Despite decades of research, there’s no viable roadmap for how to scale quantum cryptography to secure real-world data and communications for the masses,” according to IEEE Spectrum.
Wave723 shares their report:
A handful of companies now operate or pay for access to networks secured using quantum cryptography in the United States, China, Austria, and Japan. According to a recent industry report, six startups plus Toshiba are leading efforts to provide quantum cryptography to governments, large companies (including banks and financial institutions), and small to medium enterprises. But these early customers may never provide enough demand for these services to scale…
From a practical standpoint, then, it doesn’t appear that quantum cryptography will be anything more than a physically elaborate and costly — and, for many applications, largely ignorable — method of securely delivering cryptographic keys anytime soon. This is in part because traditional cryptography, relying as it does on existing computer networks and hardware, costs very little to implement. Whereas quantum crypto requires an entirely new infrastructure of delicate single-photon detectors and sources, and dedicated fiber optic lines. So its high price tag must be offset by a proven security benefit it could somehow deliver — a benefit that has remained theoretical at best.
Though it was supposed to replace mathematical cryptography, “Math may get the last laugh,” the article explains. “An emerging subfield of mathematics with the somewhat misleading name ‘post-quantum cryptography’ now appears better situated to deliver robust and broadly scalable cryptosystems that could withstand attacks from quantum computers.” They quote the security engineer at a New York cybersecurity firm who says quantum cryptography “seems like a solution to a problem that we don’t really have.”
The article ends by suggesting that research may ultimately be applicable to quantum computers — which could then be used to defeat math-based cryptography. But riffing on the article’s title, sjames (Slashdot reader #1,099) quips that instead of giving quantum cryptography a reboot, maybe it just needs the boot.