From the course: CompTIA Security+ (SY0-701) Cert Prep: 1 General Security Concepts
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Diffie-Hellman
From the course: CompTIA Security+ (SY0-701) Cert Prep: 1 General Security Concepts
Diffie-Hellman
The Diffie-Hellman key exchange algorithm solves the problem of key exchange for symmetric encryption. The algorithm was invented in 1976 by three cryptographers. It was based upon the work of Ralph Merkle and turned into a practical algorithm by Whitfield Diffie and Martin Hellman. Unfortunately for Merkle, his name wasn't included in the name of the algorithm and were left with the Diffie-Hellman algorithm. I'm going to show you how Diffie-Hellman works mathematically, but first I want to use an analogy to share the purpose using colors instead of numbers. I think it makes the concept a little easier to understand. Let's say that Alice and Bob want to agree upon a common shared secret color that they don't want other people to know. Here's one way that they might do that. First, Alice sends Bob a message telling him a common color that they might use. Let's say that Alice selects yellow and then tells Bob that color by email. Next, Alice and Bob each select a secret color of paint…