A Design Mechanism is a concrete representation of an Architectural Mechanism. It is refined from an Analysis Mechanism and is further refined into an Implementation Mechanism as the design becomes more detailed.
Design Mechanisms can be represented as specific design patterns and frameworks in the design. They are
used to guide development. Design Mechanisms should still be relatively independent of implementation but provide
enough detailed information for implementation choices to be made and software to be developed with confidence.
See Example: Design Mechanisms.