1. Software Engineering Institute Carnegie Mellon University Pittsburgh, PA 15213-3890 Sponsored by the U.S. Department of Defense © 2001 by Carnegie Mellon University Carnegie Mellon University Software Engineering Institute COTS Based Systems (CBS) Cost Model Overview

2. © 2001 by Carnegie Mellon University CBS Cost Model Overview - page 2 Carnegie Mellon University Software Engineering Institute Modeling Concept Based on CBS activities: Use parametric models to estimate activity effort and schedule that have variability Use averages to estimate activities that are relative constant in effort and schedule Activities are described in "An Activity Framework for COTS-Based Systems,” CMU/SEI-2000-TR-010, by Oberndorf, Brownsword, Sledge. Model is intended to be open, understandable, and flexible

3. © 2001 by Carnegie Mellon University CBS Cost Model Overview - page 3 Carnegie Mellon University Software Engineering Institute Business Activity Area COTS Business Case Vendor Relationships COTS Cost Estimation Intergovt Supplier Relationships Contract Activity Area Contract Requirements Contract Tracking & Oversight Solicitation License Negotiation Program-Wide Activity Area CBS Strategy CBS Risk Management Cultural Transition CBS Tradeoffs Information Sharing Engineering Activity Area System Context Construction Architecture and Design Configuration Management Marketplace Evaluation Deployment and Sustainment CBS Activity Set

4. © 2001 by Carnegie Mellon University CBS Cost Model Overview - page 4 Carnegie Mellon University Software Engineering Institute Model is based CBS activities Some activities are relatively constant for each COTS product, e.g. establish and maintain vendor relationships Some of the activities vary in effort depending on the type of COTS product. Variable activities are estimated with the appropriate parametric model, e.g. prototype to discover product and system characteristics

5. © 2001 by Carnegie Mellon University CBS Cost Model Overview - page 5 Carnegie Mellon University Software Engineering Institute Concept Exploration Detailed Model Concept Model High-Level Model Increasing knowledge about the product Business Case Analysis & Prototyping Production & Sustainment Modeling Scope

6. © 2001 by Carnegie Mellon University CBS Cost Model Overview - page 6 Carnegie Mellon University Software Engineering Institute Effort = (COTS-Type Average Effort)  1 Standard Deviation Schedule = (COTS-Type Average Schedule)  1 Standard Deviation COTS-Types Examples: Database GUI Builder Compiler... Concept Model Estimate (Based on an average for a COTS-Type)

7. © 2001 by Carnegie Mellon University CBS Cost Model Overview - page 7 Carnegie Mellon University Software Engineering Institute Effort = (COTS Type Average Effort)  F 1  F 2  F 3  F 4  F 5 Schedule = (COTS Type Average Schedule)  G 1  G 2  G 3  G 4  G 5 Estimate  F 1  F 2  F 3  F 4  F 5 Parametric High-Level Model Candidate Effort Influencing Factors: Suitability Availability Accessibility Experience

8. © 2001 by Carnegie Mellon University CBS Cost Model Overview - page 8 Carnegie Mellon University Software Engineering Institute Candidate Factors Affecting Effort Suitability of Using COTS Tradeoff distance Coverage of requirements Ease of tailoring Tailoring mechanisms Size of the COTS portion of the system Criticality of product to the system Architecture CBS Product Availability Number of COTS products Stability (volatility) of product Size of COTs product / number and complexity of features COTS alternatives for a component CBS Product and Marketplace Accessibility Availability of product and vendor information Vendor maturity Market segment uniformity Stability of market segment Size of market segment Technology stability CBS Development Experience Experience with CBS systems Stakeholder flexibility Life expectancy of system

9. © 2001 by Carnegie Mellon University CBS Cost Model Overview - page 9 Carnegie Mellon University Software Engineering Institute Parametric Detailed Model There are different detailed models being developed: USC-CSE COCOTS AFCC for Air Force use Others? Based on detailed model inputs, these models are used to estimate the variable effort and schedule portion of the activity set.

10. © 2001 by Carnegie Mellon University CBS Cost Model Overview - page 10 Carnegie Mellon University Software Engineering Institute Current Model Status Refining CBS activity-based model definition While the activity sets are ready for use and available, the model is still being developed Need to collect data to -establish averages for different COTS-types -validate CBS model parameters Need to compare CBS activity sets to detailed models and check their coverage

11. © 2001 by Carnegie Mellon University CBS Cost Model Overview - page 11 Carnegie Mellon University Software Engineering Institute For More Information SEI Technical Report on CBS Activity Sets is available online: http://www.sei.cmu.edu/publications/documents/00.reports/00tr010. html Activity set questions should be directed to: Tricia Oberndorf Software Engineering Institute po@sei.cmu.edu (412) 268-5412 Modeling questions should be directed to: Brad Clark Software Engineering Institute bkc@sei.cmu.edu (703) 754-0115