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 is to align IT investments with business strategy, and to keep that alignment durable as the organization changes.
Where software architecture concerns the structure of a single system, EA concerns the structure of the enterprise that owns and operates many systems. It sits above architecture and design work, supplying the cross-system context – shared standards, roadmaps, and constraints – within which individual system designs are made.
Architecture domains
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, and EA’s job is to make those ripples legible and managed rather than accidental.
Frameworks and notation
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. See architectural knowledge management for the broader practice of capturing and reusing architectural knowledge, and modeling for the techniques behind it.
Purpose and governance
The practical value of EA is in making large-scale change manageable. A mid-sized organization may run hundreds of applications; without an enterprise view, duplicates accumulate, integrations drift, and investment decisions are made in isolation. EA provides the inventory, standards, and roadmaps that let an organization steer that portfolio deliberately rather than let it accrete.
This places EA close to governance: defining which technologies and patterns are approved, how new systems are evaluated, and how the architecture evolves over time. It also overlaps with service-oriented architecture and domain-driven design at the level of individual systems, where enterprise-level standards have to be reconciled with local design decisions and the non-functional requirements of each system.