Authenticated encryption is a form of symmetric key encryption that provides confidentiality, integrity, and authenticity assurances on the plaintext. Authenticated encryption is generally constructed by combining an encryption scheme and message authentication code (MAC). An authenticated encryption can only be decrypted with the correct key. Additionally, it is impossible to alter the ciphertext without being detected. If the encryption is changed in any way then the MAC will fail to verify and decryption is aborted.