The future is fraught with disasters that scientists and engineers are desperately figuring out how to avoid—rogue artificial intelligence, climate change, nuclear war, and the subject of this article: the erosion of modern encryption by quantum computation.

The age-old cat and mouse game of hackers chasing secrets and secret-keepers coming up with better ways to protect themselves could end in a catastrophic loss by the “good guys” if advancement in quantum computing outpaces our progress in cryptography. Such a failure would mean the loss of security in all things digital; the only way to keep something safe—which is arguably already the best way today—would be to write it down in a book and defend it with your life! Or, better yet, don’t even write it down! Read some articles on extending your memory instead and keep all of your private information locked up in your brain…
…until someone figures out how to hack that too!

But often it seems, when faced with impending gloom, there is reason to be hopeful. In a poetic case of send a thief to catch a thief, Quantum cryptography might be exactly the solution we’re looking for to keep our secrets safe from Quantum code breakers.

Quantum cryptography employs the most fundamental laws of nature to beat quantum computing at its own game. Some physicists claim it can protect data against any amount of processing power, including whatever future computational beasts might bring to the table.

It’s a very exciting time. Just a few weeks ago, researchers at the Chinese Academy of Sciences and the Austrian Academy of Sciences were able to communicate from their respective continents through a quantum-encrypted conference line. The seventy-minute call was made possible by the launch of a $100 million satellite, hundreds of miles of fiber optic cables, and a team of physicists and engineers standing by to monitor the entire event.

Not the most economical way to make a phone call.
The media extravaganza was reminiscent of the first Satellite TV broadcast.

Before getting too far down the rabbit hole of quantum cryptography, it’s worth laying out a few basic principles of how the technology works and how it differs from current cryptographic techniques.
Modern cryptography is essentially built around public and private keys that are derived from massive semi-prime numbers. .

This form of securing information works because breaking it requires factoring enormous numbers into their subparts—a process that can take even the most powerful supercomputers of today hundreds of millions, if not billions of years.

The problem, of course, is that the most powerful supercomputers today are pathetic infants compared to the promises of quantum computation—.

Quantum cryptography provides protection by transmitting public and private keys through the polarization of photon particles sent via lasers and fiber optic cables. If an unauthorized party attempts to intercept and measure the signal, Heisenberg’s Uncertainty Principle tells us that the observation of the particle would change its nature and allow the corresponding parties to know that their private communication channel has been compromised.

That is the basic idea, and it may sound pretty straightforward, but there are a number of factors to be considered. Current techniques require using low-powered lasers whose signal becomes unreadable after traveling through a little less than 100 miles (160 km) of cable. That’s not a big deal if you’re less than 100 miles away from your recipient, but recall the conference call was between the Chinese and Austrian scientists. In a globalized world, any cryptography technique that becomes useless after less than 100 miles might as well not exist; at that point, you should just get into your self-driving car, nip to the other party, and tell them in person.

One solution to this problem is to use satellites to beam the signals up and down, but this presents its own problems: one of them being that the ground stations used to receive the signal have to convert it to a digital record to strengthen it and send it back out to its final destination. Anytime a quantum signal is converted into a classical digital record, the whole “quantum encryption” thing becomes a red herring and hackers use their standard toolkit to gain access to the digital signal at the receiving station.

Nevertheless, the technology is progressing and will likely become the standard for cryptography in the not so distant future. (It is rumored that .)

Without quantum cryptography and storage, the black hats will have a massive leg up in this round of the eternal technological arms race that began with stick and shield. And by ‘this round,’ think ‘foundations of the entire digital age infrastructure’!

If we do end up failing to protect ourselves against the threats of quantum computing, the consequences will be enormous. Secrets will become public and financial infrastructure will fail. Even the new world of cryptocurrency and blockchain technology will not be immune. Failing to keep up with the quantum hackers will bring blockchain technology to a screeching halt before it gets it feet under the table, making a lot of newly wealthy people very unhappy.

Perhaps for this reason alone, my money is on the good guys! Experience has shown that any issue that poses an immediate threat to banks and intelligence agencies will likely benefit from being boosted to the front of the ‘seeking urgent solutions’ queue.

Toby Weston
with thanks to Kristian Gaylord.

I hope you enjoyed this brief foray into the world of quantum espionage. Unexpected vulnerabilities revealed by advances in quantum cognition are just one of the challenges the ‘good guys’ face in the latest book in my series. If you enjoy technology inspired SciFi adventure, you might like to take a look.

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Author, Artist, and Technologist. I write to entertain, educate, and to make this deranged reality fit inside my head!