03.11.10

Bottom-up, Top-down

Posted in Control Information Technology Yourself, Enterprise Architecture, Visualization at 8:00 am by Administrator

Under the City Tour

[Cartoon]

Bottom-up in IT is considered to be looking at an organization from the technology perspective. Top-down takes a business perspective.

As an Enterprise Architect, it has been mandatory that I spend years working and learning the concepts and technologies of the IT infrastructure. This includes the message systems, the file systems, the enterprise service buses, the service interfaces, the value of synchronous versus asynchronous, the data bases (replicate or not replicate), the application servers, the security systems, the protocols, and the best design patterns. These are critical to the successful operation of an organization’s IT.

Because the concepts and technologies of the IT infrastructure continue to change, all Enterprise Architects must stay current. This is no different than any other profession where new innovations bring about improvements.

In an effort to find clarity in the enormous number of connections between business systems enabled by the infrastructure, we often draw or generate spaghetti charts. These charts show the overwhelming complexity of the flow of information in an organization, but they do not provide much clarity. They are called spaghetti charts because there are so many connections that it is difficult to find the two ends of any of the noodles.

Recently, it dawned on me that the spaghetti charts represent a bottom-up view of IT in the organization. The spaghetti chart is not a top-down view. It is a bottom-up view.

Here is where the analogy of an Enterprise Architect as a City Planner begins to pay big dividends. An Enterprise Architect, just like a City Planner, is very aware of the spaghetti of piping under the city. They both know that the piping is a requirement to run the city, but it is not the view from the top. The view from the top is the city.

For a City Planner, the top-down view is very physical. It includes laying out districts, roads, and buildings. For the Enterprise Architect, the city is real, but virtual in nature. The virtual city is made up of districts of buildings that represent the holistic view of IT.

The holistic model of IT is a top-down model. It can be used to visualize the impact of processes and changes on the organization. It is the link to all of the enterprise models: corporate, processes, data, component, and technology.