Gentle Introduction To Cryptography

Part I — Welcome to the world of Alice, Bob and the incorrigible Oscar

What is Cryptography?

Cryptography, in spite of sounding so grandiloquent, tries to solve a very fundamental problem. How do you send a message from one point to another in a very public setting, with a confidence that the message will not be understood by anyone else.

Figure 1. Alice and Bob communicating over a public channel