If you believe all of the news reports, quantum computers are here and can break Quantum Computing Mean the End of Encryption all of the encryption that we have ever used.
A bit hyperbolic.
Dorothy Denning, a very well know security researcher who has written 4 books and over 200 articles while teaching at Purdue, Georgetown and the Naval Postgraduate School wrote a very readable article on the subject.
She explains what is and what is not real and why. In English.
She makes a distinction between symetric key encryption like AES and public key encryption. For AES, there are reasonable solutions to the problem.
For public key encryption, one algorithm is based on the supposedly hard problem of factoring numbers. So far the largest number that they have factored is 15 (4 bits). Given that most public key encryption is 1,024 or 2,048 bits, they are not quite there. yet.
One study said that quantum computers would need to be 100,000 times faster and 100 times less error prone.
But they will get there.
However, the National Institute of Standards (NIST) is evaluating 69 new potential post quantum encryption algorithms. They plan draft standard by 2024 if not sooner.
So as long as quantum computers don’t get 100,000 times faster and 100 times more reliable in the next 5 years or so, we are probably OK.
Read Dr. Denning’s article here. Put your mind at ease.