By Mike Rosen

February 2021

Understanding Enterprise Architecture Domains

Multiple forces have combined to create a renewed emphasis in enterprise architecture (EA). First, organizations are more dependent on technology, which continues to expand in importance and complexity. This is compounded by the drive for digital transformation and the need for engaging customer experience and operational efficiency. Finally, COVID-19 has shown that organizations with a good architectural foundation are more successful with the tough decisions and quick changes to business and operating model that the pandemic demands.

The amount and complexity of technology has greatly expanded, and the need for it to work together is critical to digital experience. Enterprise Architecture helps organizations to understand the big picture, what all the pieces are and how they must fit together to achieve transformation, how to integrate them for consistency and interoperability, and how to balance efficiency and effectiveness against agility and flexibility. In an environment where it seems like everything has changed, architecture has also changed to keep pace with the new realities. Architecture gives us a way to understand and manage those new realities and complexity. By decomposing the whole into constituent parts, it allows organizations to address each component in a thoughtful, thorough, and coordinated manner. Then, it allows the ‘big picture context’ to frame information and improve decisions.

For enterprise architecture, the ‘big picture’ includes all aspects of the enterprise in its entire ecosystem. So, in order to manage that scope, architects divide the picture into subject areas (constituent parts), called architectural domains. Figure 1 illustrates the extended domains of enterprise architecture required to fully support digital transformation. The four horizontal domains in the center of the diagram (business, information, application, and technology) represent the traditional view of enterprise architecture. While these are still important, they no longer provide a sufficient model for enterprise IT and its relationship to business and transformation. We extend the model to include four vertical domains (security, performance, integration, and service) whose concerns span across all the traditional domains.

The vertical domains represent a different relationship than the horizontal domains which build on top of each other through a layered structure. Instead, vertical domains must be represented by a holistic architecture that spans all four of the traditional horizontal domains in such a way that the whole is greater than the sum of the parts. In other words, for each vertical domain, specific architectural concerns and implementations at each of the business, information, application, and technology layers must be coordinated and integrated to optimize the enterprise, rather than sub optimizing the particular layer.

The bottom of the figure indicates the organizational aspects of architecture. In other words, architects express the architecture domains in architectural artifacts that are produced by an architecture program as part of some organizational structure. Enablement, helping stakeholders use architecture to influence decisions, is a key focus of architecture teams.