Step: Qualify analysis mechanisms

If the analysis class uses one or more analysis mechanisms, additional information captured now will assist the architect and designers determine the capabilities required of the architectural design mechanisms.  The number of instances of the analysis class, their size, their frequency of access, and their expected life-span are among the important properties that can assist the designers in selecting appropriate mechanisms.

For each analysis mechanism used by the analysis class, qualify the relevant characteristics which need to be considered when selecting appropriate design and implementation mechanisms.  These will vary depending on the type of mechanism; give ranges where appropriate, or when there is still much uncertainty.  Different architectural mechanisms will have different characteristics, so this information is purely descriptive and need only be as structured as necessary to capture and convey the information.   During analysis, this information is generally quite speculative, but capturing has value since conjectural estimates can be revised as more information is uncovered.

The analysis mechanisms used by a class and their associated characteristic need not be captured in a formal way; a note attached to a diagram, or an extension to the description of the class is sufficient to convey the information.  The characteristic information at this point in the evolution of the class is quite fluid and speculative, so the emphasis is on capturing expected values rather than on formalizing the definition of the mechanisms.

Example

The characteristics of the persistence mechanism used by a Flight class could be qualified as:

Granularity: 2 to 24 Kbytes per flight

Volume: Up to 100,000

Access frequency:

• Creation/deletion: 100 per hour
• Update: 3,000 updates per hour
• Read: 9,000 access per hour

Example

The characteristics of the persistence mechanism used by a Mission class could be qualified as:

Granularity: 2 to 3 Mbytes per mission

Volume: 4

Access frequency:

• Creation/deletion: 1 per day
• Update: 10 per day
• Read: 100 per hour