Quantum Computing

Encrypting with Symmetric Keys

In cryptography, messages are encrypted using keys, which are strings to make the original message gobbledygook. Broadly speaking, the keys are of two types:

• Symmetric key algorithms where both the sender and receiver use the same key to encrypt and decrypt messages. In classical cryptography, the Advanced Encryption Standard (AES)^[50] is a widely used symmetric key algorithm.

• Asymmetric Key algorithms use different keys for encrypting and decrypting messages. These algorithms, such as RSA,^[51] are also called public/private key algorithms since one of the keys is publicly known. Using the public key, anyone can encrypt a message, but only the intended receiver can decrypt it based on the private key. These ...