Realizing the need for asymmetric encryption

We use symmetric encryption to secure our data transactions using a single shared secret key. When using symmetric encryption, it's best practice to change the key often to prevent it from being compromised. As a result, we need to generate and distribute the secret key securely to both parties when needed.

Because symmetric encryption uses a shared secret key, the question remains: how do both parties securely obtain the same key? The answer is to use a hybrid system that employs both symmetric and asymmetric encryption.

The components for asymmetric encryption, such as plaintext, ciphertext, and the encryption algorithm are similar to those used in symmetric encryption. However, instead of using the same shared key, asymmetric encryption uses two keys, a public and a private key, as shown in the following diagram:

Figure 5.1 – Asymmetric key pair

The two keys are mathematically related...