3. Asymmetric cryptography

Public key (asymmetric) cryptography was invented by Diffie and Hellman in their seminal paper . They sought to solve the problem of key exchange. How to exchange a secret key without having to meet each other?

They defined the notion of one-way function, central to cryptography today. One-way functions are functions for which there is an efficient algorithm for calculating the image of a point, but no efficient algorithm for inverting the function