!!! Overview
[{$pagename}] key exchange ([DH]) is a specific method of securely [Key-Exchange] over a public channel and was the first specific [example] of [Public Key Cryptography] as originally conceptualized by [Ralph Merkle].

[{$pagename}] is one of the earliest practical [examples] of [Public Key] exchange implemented within the field of [cryptography]. The [{$pagename}] [Key-Exchange] method allows two parties that have no prior knowledge of each other to jointly establish a shared secret key over an insecure communication channel. This key can then be used to encrypt subsequent communications using a [Symmetric Key] [Cipher].

The scheme was first published by [Whitfield Diffie] and [Martin Hellman] in [1976|Year 1976].

By [1975|Year 1975], James H. Ellis,[3] Clifford Cocks and Malcolm J. Williamson within GCHQ, the British signals intelligence agency, had also shown how [Public Key Cryptography] could be achieved; however, their work was kept secret until [1997|Year 1997].

Although [{$pagename}] [Key agreement] itself is an anonymous (non-authenticated) key-agreement protocol, it provides the basis for a variety of authenticated [protocols], and is used to provide [Perfect Forward Secrecy] in [Transport Layer Security]'s [Ephemeral] modes (referred to as EDH or DHE depending on the [Cipher Suite]).

The method was followed shortly afterwards by [RSA], an implementation of [Public Key] cryptography using [Asymmetric Key Cryptography].

U.S. Patent 4,200,770, from [1997|Year 1997], is now expired and describes the now [Public Domain] [algorithm]. It credits Hellman, Diffie, and [Merkle|Ralph Merkle] as inventors

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* [#1] - [Diffie–Hellman key exchange|Wikipedia:Diffie–Hellman_key_exchange|target='_blank'] - based on 2015-03-18