Contents
In brief
Shor’s algorithm and Grover’s algorithm are the two results worth understanding before you listen to a broader claim. They do not do the same kind of work.
Original CloudExchangers explainer. It describes established public practice and labels the desk’s judgment as analysis. It is not a report of a newly announced event.
Two famous results, two different promises
Shor’s algorithm gives a quantum computer a route to factoring and related problems that is efficient in a way the best known classical algorithms are not. That is why public-key schemes built on those problems are the subject of a migration, and why NIST has a post-quantum cryptography project for replacement algorithms that run on ordinary computers. The result is about a future machine large and stable enough to run the algorithm on cryptographic sizes. It is not a description of a device you can rent this afternoon and point at your TLS keys.