# Symmetric Encryption

### What is encryption?

Encryption is the conversion of data (plain text) into a form that is unreadable (ciphertext). Encryption allows us to protect data during transmission and make it useless if hacked from a server.

The process of encryption involves secret encryption/decryption keys and an encryption algorithm.

Encryption keys consist of a combination of letters and numbers.

The longer the key, the harder it is to figure out, e.g. a 256 bit key is more secure than a 128 bit key.

### Symmetric encryption

Symmetric encryption uses the same secret key to encrypt and decrypt the data.

**Drawback**

Using the same key to encrypt and decrypt creates a problem known as the key distribution problem.

In order to decrypt your ciphertext data, the receiver will need a copy of your secret key.

Sending the secret key over the internet causes a serious security risk – a hacker could intercept the key and decrypt the ciphertext data too!

Other than physically transporting the key yourself, there is a solution to the key distribution problem. It’s called asymmetric (or public key) encryption.