Key takeaways
- Baseline = an agreed specification changed through formal control; it is not just the current state.
- One or more Transition Architectures may separate Baseline and Target; they appear in the Architecture Definition Document.
- The Architecture Vision summarizes the target, its value, and expected changes, and bounds detailed work.
- Gap = difference; Work Package = actions; Roadmap = abstracted multi-year plan.
Describing states
The word Baseline means more than 'current state'. It refers to any formally reviewed and agreed specification that becomes the basis for later work and is then changed only through a formal change control or configuration management procedure. An agreed Target Architecture therefore also acts as a baseline.
The Target Architecture describes a future state of the architecture developed for the organization. The note to its definition says several future states may be developed, as a roadmap, to show the evolution toward the target. Finally, a Transition Architecture formally describes one state of the architecture at a significant moment; one or more transitions may mark the progression, and they are described in the Architecture Definition Document.
Summarizing the target: the Architecture Vision
The Architecture Vision is a succinct description of the Target Architecture that sets out its business value and the changes its deployment will bring to the enterprise. It plays two roles: an aspiration that mobilizes stakeholders and a boundary that limits detailed development. A proposal outside that scope should therefore lead to an explicit review of the Vision.
Measuring the difference and organizing change
A Gap is a statement of difference between two states; gap analysis applies it to the comparison between Baseline and Target. Gaps are then addressed by Work Packages: sets of actions identified to reach one or more business objectives. A Work Package can be part of a project, a whole project, or a program.
A Roadmap is an abstracted plan for business or technology change, usually spanning several disciplines and several years; we speak of an Architecture Roadmap or a Technology Roadmap. For a given capability, change can also be split into Capability Increments: each increment is a discrete portion of the Capability Architecture delivering specific value, and the capability is realized once all increments are delivered.
- A state: Baseline, Transition, or Target Architecture.
- A difference between states: Gap.
- Actions to close the difference: Work Package.
- A multi-year plan that orders change: Roadmap.
TERMS TO KNOW
The terms, in context.
- Baseline
- Reviewed and agreed specification, basis for later work, changed through formal change control.
- Target Architecture
- Description of a future state of the architecture developed for the organization.
- Transition Architecture
- Formal description of the architecture as it stands at one architecturally significant moment.
- Architecture Vision
- Succinct description of the target, its business value, and expected changes; aspiration and boundary for detailed work.
- Gap
- Statement of difference between two states, notably Baseline and Target.
- Work Package
- Set of actions aimed at one or more business objectives: part of a project, a project, or a program.
- Roadmap
- Abstracted plan for business or technology change, often multi-disciplinary and multi-year.
- Capability Increment
- Discrete portion of a Capability Architecture that delivers specific value.