# Outlining symmetric algorithms

When designing a cryptographic algorithm, the idea is to have an elegant and efficient cipher that secures data with an appropriate amount of confusion and diffusion. In this segment, we'll review the elements that make symmetric encryption computationally fast and capable of efficiently performing the calculations necessary to encrypt data. We'll then review AES, DES, and other algorithms used in a production network. We'll finish with a discussion on how the keys to be used in each round or iteration during encryption are generated.

Let's start by discussing the key concepts in symmetric encryption.

## Understanding symmetric encryption

The term *symmetric* means balanced or equal, which is a fitting description for symmetric encryption as it uses the same shared secret key to encrypt and decrypt text.

Symmetric encryption, also called conventional or secret key encryption, is done in a straightforward manner, using the...