Overview#

Authenticated Encryption with Associated Data (AEAD) is defined in RFC 5116 and defines a uniform interface and a registry for such algorithms.

Authenticated Encryption [1] is a form of encryption that, in addition to providing confidentiality for the plaintext that is encrypted, provides a way to check its authenticity.

Authenticated Encryption with Associated Data, or AEAD, adds the ability to check the integrity and authenticity of some Associated Data (AD), also called "additional authenticated data", that is not encrypted.

RFC 5116 also defines an Authenticated Encryption with Associated Data (AEAD) Parameters IANA Registry

Why use "Associated Data"#

As a very general rule, the purpose of Associated Data (hereafter "AD") is to bind a ciphertext to the context where the it is supposed to appear, so that attempts to "cut-and-paste" a valid ciphertext into a different context can be detected and rejected.[3]]

More Information#

There might be more information for this subject on one of the following:

• AEAD
• AEAD_CHACHA20_POLY1305
• CHACHA20-POLY1305
• EAX
• Network Time Protocol
• Network Time Security
• RFC 5116
• TLS 1.2
• TLS 1.3

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• [#1] - Authenticated encryption: Relations among notions and analysis of the generic composition paradigm - based on information obtained 2016-02-16
• [#2] - Authenticated-Encryption with Associated-Data - based on information obtained 2016-02-16
• [#2] - What is the purpose of associated authenticated data in AEAD? - based on information obtained 2018-02-08-