# TLS/SSL Terminology and Acronyms

Table 1: TLS/SSL Terminology provides definitions of TLS/SSL terminology:

Term |
Definition |

Plaintext |
The original, unencrypted data. |

Ciphertext |
The encrypted data. |

Cryptography |
The practice of secure communications. |

Encryption |
The process of turning plaintext into ciphertext. |

Decryption |
The process of turning ciphertext into plaintext. |

Encryption algorithm |
The algorithm used to perform encryption and decryption. It is also called the cipher. |

Encryption key |
The key used for encryption. |

Decryption key |
The key used for decryption. |

Symmetrical encryption algorithm |
The algorithm used for encryption in which the encryption key and the decryption key are identical. |

Asymmetrical encryption algorithm |
The algorithm used for encryption in which the encryption key and the decryption key are different. |

Public key |
The key used for encryption. |

Private key |
The key used for decryption. |

Table 2: TLS/SSL Acronyms lists TLS/SSL acronyms:

Acronym |
Definition |

AES |
Advanced Encryption Standard |

CA |
Certificate Authority |

CBC |
Cipher Block Chaining |

CN |
Common Name |

CRL |
Certificate Revocation List |

DES |
Data Encryption Standard |

DH, D-H |
Diffie-Hellman |

DSA |
Digital Signature Algorithm |

ECDH |
Elliptic Curve Diffie-Hellman |

ECDSA |
Elliptic Curve Digital Signature Algorithm |

FQDN |
Fully Qualified Domain Name |

IDS |
Intrusion Detection System |

IPS |
Intrusion Prevention System |

MAC |
Message Authentication Code |

MD |
Message Digest |

MitM |
Man-in-the-Middle |

OCSP |
Online Certificate Status Protocol |

OoB |
Out-of-Band |

PEM |
Privacy Enhanced Mail |

PFS |
Perfect Forward Secrecy |

PKCS12 |
Public Key Cryptography Standard #12 |

PKI |
Public Key Infrastructure |

RSA |
Rivest-Shamir-Adleman |

SHA |
Secure Hash Algorithm |

SSL |
Secure Sockets Layer |

TCP |
Transmission Control Protocol |

TLS |
Transport Layer Security |

URL |
Uniform Resource Locator |