What is IT Architecture?

If you enter 'IT Architecture' into Google, don't bother pressing the I'm Feeling Lucky button because where you'll land is on a web site that's got absolutely nothing to do with IT. What you'll find, instead, may be of interest if you're designing buildings, but it won't help you one iota if what you're trying to do is design IT systems.

Unfortunately, clicking the Google Search button won't offer you much more assistance, not unless what you're looking for are "Sponsored Links", the majority of which will direct you to pages pertaining to 'Enterprise Architecture'.

Assuming, like me, you prefer your Google results unsponsored, let's try searching on 'Enterprise Architecture' directly. At least that search will return results relevant to IT. The first item retrieved directs you to the following web site:

There, you'll find the Institute For Enterprise Architecture Developments' version 1.4 of its Extended Enterprise Architecture Framework. For a detailed view of IFEAD's model, click on the following image:

While quite similar to the Zachman Framework, I believe the above graphic represents a significant improvement because it contains fewer rows. In articles I've written for FTP's Enterprise Architect magazine, I've complained that the biggest problem with the Zachman approach is deciding in which row something belongs. As you move down from the top to the bottom of the Zachman Framework, the boundaries between the rows appear to become ever more arbitrary. I've attributed this problem primarily to John Zachman's personal lack of experience in actually developing software systems. Please don't infer from this criticism that I reject everything Zachman advocates. Quite the contrary. I've always applauded John's idea that the fundamental purpose of Enterprise Architecture is twofold:

1. Document everything about IT
2. Model everything about IT

It's just that on these two points, I prefer to reverse the ordering, placing higher emphasis on modeling. That's why I was so disappointed to discover that what I consider to be the best Enterprise Architecture model, TOGAF (The Open Group Architecture Framework), doesn't even appear until you get to the bottom of page 7 of Google's search results.

TOGAF defines four types of architecture that are subsets of an overall Enterprise Architecture.

1. Business Architecture
2. Data Architecture
3. Application Architecture
4. Technology Architecture

The first three subsets are pretty universally understood. Business Architecture describes business processes. Data Architecture defines entities (aka objects). Application Architecture specifies solutions which are comprised of a little bit of process and little bit of data. But what about Technology Architecture? What exactly is it? My experience has been that most IT professional have a really tough time defining Technology Architecture. I've spent considerable energy trying to precisely define this term. My analysis has led me to conclude that Technology Architecture corresponds to an organization's technology portfolio.

A technology portfolio consists of all the IT products purchased by an enterprise. The goal is to figure out how best to organize all this information. In my opinion, the best way to do this is by using a three-layer, four-model representation as illustrated below:

The bottom layer corresponds to IT Infrastructure. While extremely expensive and complex, IT Infrastructure, by itself, really doesn't do much of anything. It just sits there. Value is derived only after Applications get layered on top. Depicted as the middle layer in the graphic above, applications can either be developed or purchased. Of course, regardless of whether they're built or bought, applications generate data -- data that yearns to analyzed and mined for its Business Intelligence. That's the top layer of Technology Architecture.

The ITscout web site provides an interactive environment where you can explore these four models:

1. IT Infrastructure Roadmap (bottom row)
   
2. Application Development Roadmap (middle row)
   
3. COTS Application Roadmap (middle row)
4. Business Intelligence Roadmap (top row)
   

In future posts I'll delve into more details about Technology Architecture as well as the four ITscout roadmaps.