This tutorial (along with the others in this series) targets programmers who want to familiarize themselves with cryptology, its techniques, its mathematical and conceptual basis, and its lingo. The ideal user of this tutorial has encountered various descriptions of cryptographic systems and general claims about the security or insecurity of particular software and systems, but may not entirely understand the background of these descriptions and claims. Additionally, many users will be programmers and systems analysts whose employers have plans to develop or implement cryptographic systems and protocols (perhaps assigning such obligations to the very people who will benefit from this tutorial).

Part 1 of this three-part tutorial, here on developerWorks, introduced the very basic concepts of cryptography (for example, what encryption is and what keys are). Part 1 also covered the basic notions of cryptanalysis -- at least enough to help you understand some typical attacks and what it is to break a protocol.

Part 2 (this tutorial) introduces readers to intermediate cryptographic concepts. Users should feel comfortable with these introductory notions (Part 1 is a good starting point for those not already familiar with these concepts).

In this tutorial, I'll cover cryptographic algorithms and protocols. The goal is not to cover the coding and detailed workings of specific algorithms and protocols, but rather to give users the conceptual background necessary to understand and construct cryptographic algorithms and protocols. Upon completing this tutorial, you will have most of the building blocks needed to consider cryptography.