We urgently need to prepare for quantum computers breaking encryption

Something very bad is going to happen in the near future unless we change course. Researchers know what will cause it and roughly when it will happen, and have ideas to mitigate it. Yet policy-makers may not do enough to avert it in time.

This could be describing climate change, or perhaps the early days of the covid-19 pandemic. Now, it also applies to something more esoteric:
quantum computers. As we report here, two separate papers, including one from Google, have discovered that the threshold for a quantum computer to threaten the encryption that keeps our data safe is far lower than expected.

The knowledge that quantum computers will one day be able to quickly solve the maths problems that underpin our security isn’t new – it is perhaps one of the
few well-grounded applications of these exotic machines. What is new is that this moment, labelled Q-Day by some, may be far closer than anyone expected. Should it arrive unbidden, the results will be catastrophic: emails hacked, bank accounts emptied and secrets spilled.

Thankfully, we already have a solution. For decades, researchers have been developing “post-quantum” cryptography (PQC) based on mathematical problems hard enough to resist even beefy quantum machines. Indeed, Google, in a perhaps-not-coincidental move, now plans to transfer its services to PQC by 2029 – soon enough to shock some observers.

These developments should stir policy-makers into action. Of those governments that have set deadlines for implementing PQC, including the US, the UK and the European Union, most are aiming for 2035. That is beginning to look quite tardy.

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Ironically, many of these governments have spent the past few decades waging a war on encryption, attempting to implement “backdoors” they say would allow for better law enforcement, though such efforts have thankfully been resisted. A mismanaged Q-Day would grant these anti-encryption wishes – and wreak havoc on the modern world. We must prepare, before it is too late.