Enterprise Architecture Definitions

As there are numerous definitions of SOA, there are also numerous definitions of Enterprise Architecture. Like with SOA, one may derive a definition of EA from reading between some of the definitions provided in many of the popular EA/SOA books


From these definitions, I get the idea that Enterprise Architecture is:

The current definition of an enterprise's business processes and the information technologies that aid in their execution. The Enterprise Architecture is a dynamic form of documentation which is subject to change in the short and long term due to changes in both business and technology. EA is a road map for the Enterprise concerning business process and technology to make IT a strategic asset.

Two of the main EA Frameworks I have looked at deal with it in different ways. The Zachman Framework seeks to classify the Enterprise by mapping Enterprise components into one of 36 classification squares. TOGAF presents an ADM(Architectural Development Cycle) which is an iterative cycle of how to define the Enterprise Architecture.


The definitions below are taken from my research in to SOA and Enterprise Architecture. I do not think it coincidence that so many of the SOA books mention Enterprise Architecture. They do complement one another. Maybe one could say that SOA is a style of architecture to help make Enterprise Architecture better. Or maybe Enterprise Architecture can tell the enterprise what to build with SOA. The two concepts are apparently strongly linked.

On Todd Biske's blog, he mentions a quote from David Linthicum on SOA and EA.

"Five years from now, we won’t be talking about SOA… It will all be folded back into EA." - David Linthicum


Enterprise Architecture Definitions:

“The enterprise architecture is the organizing logic for business processes and IT infrastructure, reflecting the integration and standardization requirements for the company’s operating model. The enterprise architecture provides a long-term view of a company’s processes, systems, and technologies so that individual projects can build capabilities – not just fulfill immediate needs”1

“In simple terms, an Enterprise architecture identifies the main components of the organization and the ways in which these components work together in order to deliver the product and achieve the business objectives at the same time”.2


“You must recognize that the enterprise architecture is not static – it is constantly changing as business needs vary and technologies evolve. The task of the enterprise architecture group is to guide this evolution. To do so requires that the group keep one eye looking toward the future and the other focused on the realities of the present, while continually striving to draw the two together. Managing this evolution requires understanding the current state, articulating a vision for the future, and defining a roadmap for getting from here to there”3


“Enterprise Architecture is basically a discipline of IT architecture where we are concerned with IT in the context of the company as a whole – both IT and business”4

“An architecture description is a formal description of an information system, organized in a way that supports reasoning about the structural properties of the system. It defines the components or building blocks that make up the overall information system, and provides a plan from which products can be procured, and systems developed, that will work together to implement the overall system. It thus enables you to manage your overall IT investment in a way that meets the needs of your business.”5

“An enterprise architecture specification is to an organization what an urban plan is to a city. Therefore, the relationship between an urban plan and the blueprint of a building are comparable to that of enterprise and application architecture specifications.” 6


References:
1.Ross, Weill, Robertson,”Enterprise Architecture As Strategy”, 2006, p. 9
2.Grigoriu, “An Enterprise Architecture Development Framework”, 2006, p.22
3.Brown, “Succeeding with SOA”, 2007, p 115-116
4.Bloomberg,Schmelzer, “Service Orient or Be Doomed!”, p.121
5.The Open Group, TOGAF The Open Group Architecture Framework 2006 Edition
6.Thomas Erl,”Service-Oriented Architecture(Concepts, Technology, and Design)”, 2006, p. 87