1

Create Utility Tree

• Examine quality of service requirements and product requirements to determine the key drivers of quality and function in the application.
• Construct a utility tree that represents the overall quality of the application. The root node in the tree is labeled Utility.
• Subsequent nodes are typically labeled in standard quality terms such as modifiability, availability, security. The tree should represent the hierarchical nature of the qualities and provide a basis for prioritization.
• Each level in the tree is further refinement of the qualities. Ultimately the leaves of the tree become scenarios.

2

Construct Assessment Matrix

• For each leaf in the utility tree, write a scenario. The scenario is in the form of context, stimulus, and response. For example, "Under normal operation, perform a database transaction in fewer than 100 milliseconds."
• Open the assessment matrix template. Enter each scenario as a row in the assessment matrix.
• Enter each architectural strategy as a column. The intersection of strategies and scenarios are the cells where each strategy is rated against a scenario.

3

Rate Strategies

• Review the matrix and evaluate each cell in terms of value, development cost, and operations cost. Each rating is either low, low-medium, medium, medium-high, or high.
• Value is the overall quality of the solution that will be derived from applying the strategy to the scenario and also incorporates an assessment of risk.
• Development cost is the effort expected to realize the scenario in the context of the strategy.
• Operations cost is the expected run-time efficacy of the strategy in the context of the scenario.
• If a proof of concept has been built for a strategy, use information from that proof of concept to help determine the value, development cost, and operations cost.

4

Normalize Matrix

• Review the matrix a second time and calculate a rating number for each cell. Use the provided rate table in the assessment matrix template to calculate the numbers. For example, a cell with a value of Moderate (1), development cost of High (0), and operations cost of Low (2) equals a total rating number of 3.
• Upload the completed assessment matrix to the project portal.

Architecture assessment matrix is created.