How many keys is required for symmetric key encryption?

The encryption is called “symmetric” because it uses a single key for both encryption and decryption. In comparison, asymmetric key encryption, also called public key cryptography, uses two separate keys to encrypt and decrypt messages. A key is a random string of binary digits or bits created specifically to scramble and unscramble data.

Which is the largest disadvantage of the symmetric encryption?

Which is the largest disadvantage of the symmetric Encryption? 1. More complex and therefore more time-consuming calculations. 2. Problem of the secure transmission of the Secret Key. 3. Less secure encryption function. 4. Isn't used any more. Answer 2 is correct.

Does asymmetric encryption involves keys?

Asymmetric encryption uses two separate keys which are mathematically involved with each other. The first key is called the private key. The private key is the one that is heavily protected. Often this key remains in an HSM or an air-gapped computer to ensure the protection of the private key.