An Enterprise Architecture (EA) is a strategic information asset base, which defines the mission, the information necessary to perform the mission, the technology necessary to perform the mission, and the transitional processes for implementing new technologies in response to the changing mission needs. An EA characterizes and models the enterprise as a set of interrelated layers or views: strategy and performance, business, data, applications and services, and technology/infrastructure.
Strategic decisions about cloud computing should both draw upon and inform the EA. An organization must have a mature and well formed understanding of its architecture components (e.g., business processes, services, applications and data) to make meaningful decisions related to cloud computing, such as whether a move to the cloud is advantageous, what services most lend themselves to a cloud deployment, and what cloud deployment model (e.g., private, public) makes the most sense.
There are three key roles for EA in facilitating cloud computing strategy and planning:
Front-end decision support. An organization's EA should inform decisions about the desirability of a move to a cloud environment, what services should move to the cloud, and the appropriate deployment models. Existing business processes, services and resources should be analyzed through the lens of cloud characteristics and quality dimensions, such as elasticity, reliability, and security.
Cloud implementation planning support. During the period of transition, an EA provides the current inventory of services and the roadmap to which services are being deployed into what clouds. As new business needs emerge, the EA provides solution architects with a view of what has been deployed in the cloud already and what is planned for future deployment.
Enterprise context. Sharing and reuse of services and resources long have been primary objectives of EA. In the context of a cloud strategy, EA provides a critical enterprise view to ensure cloud decisions are optimized at the enterprise level and independent decisions on cloud-based point solutions are viewed in a broader context.