Did you know there's a secret handshake for computers?
Whitfield Diffie
Did you know there's a secret handshake for computers?
Imagine you want to send a secret note to a friend without anyone else reading it. You need a way to share a secret key with them securely.
Whitfield Diffie and Martin Hellman's idea is like creating a secret handshake that only you and your friend know. This secret handshake is called the Diffie–Hellman key exchange.
Example
You and your friend agree on a secret starting point (like saying "three apples" instead of "three"). You each add a secret number to this starting point (like adding "two" to "three apples"). You exchange what you got and then subtract your secret number to find the secret starting point. Now, both of you can use this secret starting point to create a secret key for your note.
Remember this
The secret handshake (Diffie–Hellman key exchange) allows you and your friend to share a secret key securely, even if someone else tries to listen in.
Text adapted from Wikipedia, licensed under CC BY-SA 4.0.
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