Symmetric Encryption

Cryptography · Intermediate

Encryption in which the same secret key both locks and unlocks the data. It is fast, but every party must protect that shared secret.

Both sides share one key. That works well for large amounts of data, but you need a safe way to get the same secret to both parties.

Example: AES is a common symmetric algorithm. A full-disk product uses it with a key that never leaves the protected device unprotected.

Common misconception

Using one shared secret is not a weakness by definition. The weakness is distributing and storing that secret badly.