Decrypting Crypto: An Introduction to Cryptography (W00a)
Cryptography is an interesting subject and a very important one when you are talking about security. But it is also a complicated topic and with all of the different rules, standards, algorithms, key lengths and methods, it can be daunting to learn. This tutorial will introduce you to the basics. First we’ll talk about the history of sending secret messages and then we’ll explore the various mechanisms used historically, to give you some background. We’ll work through the concepts of symmetric and asymmetric algorithms and hashing, finally talking about combining these basic building blocks to make the protocols, like SSL (Secure Sockets Layer), which all of us use every day as part of normal Internet and Web activity. Lastly we’ll dig a little deeper to talk about how cryptography works with standards, what “approved functions” are and we’ll delve into the choices (some you get to make, and some that are made for you) of which algorithms, methods, key lengths and protocols we use in modern security products.