What is "harvest now, decrypt later"?
Recording encrypted data today in order to decrypt it once a capable quantum computer exists.
Encrypted traffic can be copied as it crosses the internet and stored cheaply. If it was protected with RSA or elliptic curves, a future quantum computer could unlock it.
This matters for anything that must stay secret for a long time: medical records, state secrets, trade secrets. It’s the main reason to switch to post-quantum cryptography before quantum computers can break anything.
Related
- Q-DayThe day a quantum computer can break the public-key encryption in wide use today, such as RSA-2048 or 256-bit elliptic curves.
- Post-quantum cryptographyEncryption that runs on ordinary computers and is designed to resist attacks by quantum computers.
- RSAA public-key encryption method from 1977 whose security relies on how hard it is to factor the product of two large primes.