Checkpoints: Design Model
Topics
General 
- The objectives of the model are clearly stated and visible.
- The model is at an appropriate level of detail given the model objectives.
- The model's use of modeling constructs is appropriate to the problem at hand.
- The model is as simple as possible while still achieving the goals of the model.
- The model appears to be able to accommodate reasonably expected future change.
- The design is appropriate to the task at hand (neither too complex nor too advanced)
- The design appears to be understandable and maintainable
- The design appears to be implementable
Layers
- There are no more than seven (plus or minus two) layers.
- The rationale for layer definition is clearly presented and consistently applied.
- Layer boundaries are respected within the design.
- Layers are used to encapsulate conceptual boundaries between different kinds of services and provide useful abstractions which makes the design easier to understand.
