Phase D is the Phase in TOGAF that develops the Technology Architecture for an architecture project. Technology architecture is a description of the structure and interaction of the platform services, and logical and physical technology components.
Phase D develops the Target Technology Architecture that enables the data and application components (developed in Phase C), which in turn enable the business components.
The architectures developed in Phases B, C and D combine to enable the Architecture Vision – which addresses stakeholder concerns and the Request for Architecture Work.
As with the other architecture development phases, Phase D identifies candidate Architecture Roadmap components to make the transition from Baseline to Target.
The steps in Phase D are almost identical to the steps in Phases B and C – the main difference is that the focus is now on Technology. So this includes Technology Reference Models and Technology criteria or measurements – such as Performance, Maintainability, Location and Latency, or Availability.
It’s very important to identify outputs and deliverables to help build a Technology Architecture that truly enables the Information Systems and Business Architectures.
Getting the right scope accelerates pay-back, while an excessively large scope will frustrate a successful implementation. This is not about deploying technology for its own sake, but developing a Technology Architecture that really does address the Architecture Vision and Request for Work.
Enterprise Architecture TOGAF Video