Asymmetric encryption uses a special pairing of keys:
- Provided by the recipient
- It can be given to anyone who wishes to send encrypted data to the recipient
- Safe to share as all it can do is encrypt data
- Remains private on the computer, never sent or shared
- Only this key can decrypt the data encrypted using the public key
SSL uses a combination of symmetric and asymmetric encryption:
Asymmetric encryption is used to encrypt a symmetric encryption key, thus resolving the key distribution problem.
It is better to ultimately transmit data using symmetric encryption because it is faster.
- A symmetric key is encrypted by the sending computer using the public key sent by the receiving computer (usually via SSL certificate)
- The encrypted symmetric key is sent to the receiving computer (unreadable if intercepted)
- Using the stored private key, the receiving computer decrypts the symmetric key
- Now, both computers have the same symmetric key ready for secure encrypted data transmission