The art or science, or system, of coding or ciphering data into symbolic form to disguise, and thereby secure, the contents of a message. Generally in the form of firmware, rather than software, encryption logic commonly both scrambles and compresses message units (e.g., blocks or packets) prior to transmission. The receiving device is equipped with the necessary logic to decompress and decrypt the data. Private key is a symmetric encryption method that uses the secret same key to encrypt and decrypt data. Public key is an asymmetric encryption method with an encryption (encoding) key that can be used by all authorized network users and a decryption (decoding) key that is kept secret. Encryption algorithms and mechanisms used in telecommunications include Advanced Encryption Standard (AES), Data Encryption Standard (DES), RSA, and Triple DES. See also AES, algorithm, block, code, cryptography, DES, message unit, packet, RSA, scramble, security, steganography, and Triple DES.