Secret Color Exchange
Learn how to establish a shared secret in public, based on the Diffie-Hellman key exchange.
Imagine you and a friend want to create a secret code that only you two know, but you can only talk through a phone that someone else is listening to. This puzzle shows you how to solve this impossible-sounding problem using the magic of mathematics! The Diffie-Hellman key exchange, invented in 1976, is one of the most important discoveries in cryptography and is used to secure internet communications worldwide.
The Challenge: A Secret Color
Alice and Bob want to agree on a secret color, but Eve is listening to their conversation. Can you help them establish a secret color without Eve figuring it out? Think of it like mixing paint colors - when you mix two colors together, it's very hard to figure out what the original colors were!
Alice (You)
Alice's Private Color (Secret)
Public Channel
Base Color (g=3)
Bob
Bob's Private Color (Secret)
Value: 81