What is Asymmetric (public key) encryption?
In short
Asymmetric encryption uses a pair of mathematically related keys: a public key that anyone can have and a private key that only its owner holds. Data encrypted with one key can only be decrypted with the other.
Key takeaways
- For confidentiality, the sender encrypts with the recipient's public key.
- For a digital signature, the sender signs with their own private key, and anyone can verify it with the sender's public key.
- Symmetric encryption uses one shared key; it is faster but the key must be exchanged securely.
Where it's tested
ISC: Information Security Fundamentals — study notes, a five-minute revision sheet and practice questions.
Practise: 3 questions
Question 1 of 3 · 0 answered
To send a confidential message that only the intended recipient can read, which key should the sender use to encrypt it?