Key takeaways
- Iteration concerns the Landscape, the development of an architecture, and the architecture capability.
- Phases B, C, and D are often run in parallel to manage their dependencies.
- The four iteration cycles are Architecture Context, Architecture Definition, Transition Planning, and Architecture Governance.
- Each Landscape cycle starts at Phase A and stays bounded by its Request for Architecture Work.
- One project may trigger another project with its own ADM cycle.
Three uses of iteration
The standard distinguishes three reasons to iterate. The first is to build a complete Landscape step by step: each initiative gets its own cycle, limited by its Request for Architecture Work. The second concerns development itself: activities from different phases interact to produce an integrated architecture. The third is about changing the Architecture Capability, that is, how the architecture function is organized and equipped.
These uses combine. One enterprise can have several projects running through the ADM at the same time, at different levels, while the central team adjusts its processes after learning from earlier cycles.
- Landscape iteration: complete cycles, starting at Phase A, each bounded by a request
- Development iteration: several phases active together within one cycle
- Capability iteration: evolving architecture organization, processes, and tools
Iterating within a cycle
Inside a cycle, three patterns recur. Phases may run simultaneously, especially B, C, and D, because a business decision changes the needs for data, applications, and technology, and vice versa. A project may also cycle between phases in planned cycles when no higher-level architecture provides context and constraints: it converges step by step on a detailed Target. Finally, work products already produced may be updated with new information, typically when implementation details force a review of priorities and an Architecture Roadmap or Implementation and Migration Plan must become truly executable.
Iteration also exists inside a single phase: a model may be revised several times before it settles. What matters is keeping a clear status for each product (draft, approved, revised) and going through change management to modify something already approved.
Four iteration cycles
The standard groups the phases into four cycles, each of which can be repeated. A team can iterate within one cycle without going round the whole circle, then move on to the next when the result is good enough.
- Architecture Context (Preliminary and A): establish the approach, principles, scope, and vision
- Architecture Definition (B, C, D): produce architecture content by cycling through or integrating the domains
- Transition Planning (E, F): build formal change roadmaps
- Architecture Governance (G, H): oversee implementation and manage change toward the target
When one project triggers another
Cycles are not isolated. A project may initiate another when a high-level initiative reveals an opportunity that needs more detailed architecture, or when a project discovers a Landscape impact outside its own request. Concurrent projects then have explicit relationships, and governance makes sure they neither overlap nor contradict each other.
TERMS TO KNOW
The terms, in context.
- Architecture Development iteration
- Iteration within one cycle, where several phases run together or are revisited.
- Architecture Context
- Iteration cycle covering the Preliminary Phase and Phase A.
- Architecture Definition
- Iteration cycle covering Phases B, C, and D to produce content.
- Transition Planning
- Iteration cycle covering Phases E and F to plan change.
- Architecture Governance (cycle)
- Iteration cycle covering Phases G and H to govern change.