TS.SP 1.1 Develop Alternative Solutions and Selection Criteria

Alternative solutions should be identified and analyzed to enable the selection of a balanced solution across the life of the product in terms of cost, schedule, performance, and risk. These solutions are based on proposed product architectures that address critical product quality attribute requirements and span a design space of feasible solutions. Specific practices associated with the Develop the Design specific goal provide more information on developing potential product architectures that can be incorporated into alternative solutions for the product.

Alternative solutions frequently encompass alternative requirement allocations to different product components. These alternative solutions can also include the use of COTS solutions in the product architecture. Processes associated with the Requirements Development process area would then be employed to provide a more complete and robust provisional allocation of requirements to the alternative solutions.

Alternative solutions span the acceptable range of cost, schedule, and performance. The product component requirements are received and used along with design issues, constraints, and criteria to develop the alternative solutions. Selection criteria would typically address costs (e.g., time, people, money), benefits (e.g., product performance, capability, effectiveness), and risks (e.g., technical, cost, schedule). Considerations for alternative solutions and selection criteria include the following:

• Cost of development, manufacturing, procurement, maintenance, and support,
• Achievement of key quality attribute requirements, such as product timeliness, safety, reliability, and maintainability
• Complexity of the product component and product-related lifecycle processes
• Robustness to product operating and use conditions, operating modes, environments, and variations in product-related lifecycle processes
• Product expansion and growth
• Technology limitations
• Sensitivity to construction methods and materials
• Risk
• Evolution of requirements and technology
• Disposal
• Capabilities and limitations of end users and operators
• Characteristics of COTS products

The considerations listed here are a basic set; organizations should develop screening criteria to narrow down the list of alternatives that are consistent with their business objectives. Product lifecycle cost, while being a desirable parameter to minimize, can be outside the control of development organizations. A customer may not be willing to pay for features that cost more in the short term but ultimately decrease cost over the life of the product. In such cases, customers should at least be advised of any potential for reducing lifecycle costs. The criteria used to select final solutions should provide a balanced approach to costs, benefits, and risks.

Example Work Products

1. Alternative solution screening criteria
2. Evaluation reports of new technologies
3. Alternative solutions
4. Selection criteria for final selection
5. Evaluation reports of COTS products

Subpractices

1. Identify screening criteria to select a set of alternative solutions for consideration.

2. Identify technologies currently in use and new product technologies for competitive advantage.

The project should identify technologies applied to current products and processes and monitor the progress of currently used technologies throughout the life of the project. The project should identify, select, evaluate, and invest in new technologies to achieve competitive advantage. Alternative solutions could include newly developed technologies, but could also include applying mature technologies in different applications or to maintain current methods.

3. Identify candidate COTS products that satisfy the requirements.

The supplier of the COTS product will need to meet requirements that include the following: • Product functionality and quality attributes • Terms and conditions of warranties for the products • Expectations (e.g., for review activities), constraints, or checkpoints to help mitigate suppliers' responsibilities for ongoing maintenance and support of the products

4. Identify re-usable solution components or applicable architecture patterns.

For product lines, the organization’s core assets can be used as a basis for a solution.

5. Generate alternative solutions.

6. Obtain a complete requirements allocation for each alternative.

7. Develop the criteria for selecting the best alternative solution.

Criteria should be included that address design issues for the life of the product, such as provisions for more easily inserting new technologies or the ability to better exploit commercial products. Examples include criteria related to open design or open architecture concepts for the alternatives being evaluated.