Secret key cryptography

Secret key cryptography (also called symmetric cryptography) employs algorithms in which the key that is used to encrypt the original plaintext message can be calculated from the key that is used to decrypt the ciphertext message, and vice versa. With most symmetric algorithms, the encryption key and the decryption key] are the same, and the security of this method rests upon the difficulty of guessing the key. In order to communicate securely, the sender and the receiver must agree on a key and keep the key] secret from others. Common symmetric key algorithms include Triple Digital Encryption Standard (3DES) and the Advanced Encryption Standard (AES).