Enterprise architecture (EA)
Enterprise architecture (EA) is the discipline of analyzing, designing, and governing the structure of an entire organization as a coordinated whole. It spans the business processes an organization runs, the information it relies on, the enterprise application software portfolio it operates, and the technology infrastructure that underpins all of it.
The aim of enterprise architecture is to align IT investments with business strategy, and to keep that alignment durable as the organization changes. The practical value of EA is in making large-scale IT change manageable. A mid-sized organization may run hundreds of applications, so without an enterprise view investment decisions are made in isolation, leading to integrations drift and duplication of systems. EA provides the inventory, standards, and roadmaps that let an organization steer that portfolio deliberately.
This places EA close to governance, which is about defining at the organization level which technologies and patterns are approved, how new systems are evaluated, and how the architecture evolves over time.
Enterprise architecture operates at a higher level than software architecture, which is concerned with structure of a single software system in isolation. EA is more concerned with the structure of the enterprise that owns and operates many systems. EA supplies the cross-system context – shared standards, roadmaps, and constraints – within which individual system designs are made.
EA is supported by frameworks and modeling languages that give architects a shared vocabulary and method. TOGAF supplies a process lifecycle for developing and governing an architecture, while ArchiMate supplies a graphical notation for representing its artifacts. Both are open standards maintained by The Open Group.
EA is conventionally divided into a small number of overlapping domains. The TOGAF framework names four.
- Business architecture. The organization’s goals, processes, roles, and functions, and how they map to the capabilities the enterprise delivers.
- Data architecture. The information the enterprise uses, how it is structured, and how it flows between systems.
- Application architecture. The portfolio of applications that support the business – including an ERP suite, CRM, and HR systems – together with the services each provides and the dependencies between them.
- Technology architecture. The infrastructure – servers, networks, storage, and platforms – on which applications run.
These domains are not independent. A change in business architecture usually ripples into data, application, and technology decisions. The job of enterprise architecture is to make those ripples legible and managed, rather than accidental.