Security Encyclopedia

Symmetric Key Cryptography

Symmetric Key Cryptography also known as Symmetric Encryption is when a secret key is leveraged for both encryption and decryption functions. This method is the opposite of Asymmetric Encryption where one key is used to encrypt and another is used to decrypt. During this process, data is converted to a format that cannot be read or inspected by anyone who does not have the secret key that was used to encrypt it.

The success of this approach depends on the strength of the random number generator that is used to create the secret key. Symmetric Key Cryptography is widely used in today's Internet and primarily consists of two types of algorithms, Block and Stream. Some common encryption algorithms include the Advanced Encryption Standard (AES) and the Data Encryption Standard (DES). This form of encryption is traditionally faster than Asymmetric however it requires both the sender and the recipient of the data to have the secret key. Asymmetric cryptography does not rely on sharing a secret key and forms the basis of the FIDO authentication framework.

Symmetric Key Cryptography Video:

Source: Udacity