So, a bit of a walk back through history of computing. From mainframe days until the present, computing architectures have evolved ever closer to that envisioned to ideal end state: that of a human nervous system type functionality based on quantum mechanics and bioengineering. Now, along the way, however, much of that original architecture has been repeatedly employed, from centralized to decentralized and distributed, and back to centralized, and then ultimately, currently, to cloud.

Now, part of this evolution has included the appearance of differing software, operational characteristics. We've gone from proprietary, platform specific offered by the creators of the computing platform, open source, Windows, Linux, and then a variety of others. While the hardware has continued to advance rapidly in miniaturization with greater and greater performance, software seemingly has developed a lot slower with methodologies that have evolved more slowly as new features are introduced and exploration of their functions and utility continues. The result, of course, is that computing environments of widely variable architectures exists, many remaining in service long after they were superseded as well as much of the former architecture's features and flaws also remaining present.

So we're going to address the question as it changes from why all this diversity to, how to integrate it all. We're going to talk again about confidentiality, integrity, and availability, authentication, authorization, and auditability or accountability. We're going to look again at session management, exception management, and configuration management. This diagram highlights the results of a proper understanding of what the application is supposed to do and how to build it so that features that reinforce these six characteristics are going to be developed, understood, and designed in.