University of Southern California
Center for Systems and Software Engineering
Towards COSYSMO 2.0:
Update on Reuse
Jared Fortune, USC
Ricardo Valerdi, MIT
USC ARR 2009
Los Angeles, CA
University of Southern California
Center for Systems and Software Engineering
Outline
• COSYSMO 2.0 Introduction & Status
• Reuse Process
• Reuse of SE Artifacts
• Reuse Scenarios
• Reuse in Cost Drivers
• Organizational Impacts of Reuse
• Next Steps
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University of Southern California
Center for Systems and Software Engineering
Reuse Overview
• Systems engineering activities are support-focused
– Do not produce physical products (HW, SW, etc.)
– Produce architectures, requirements, test plans, and other
technical documents
• Systems engineering products can be viewed as
“artifacts”
– Encapsulation of systems engineering knowledge in a document
or process
– Representative of systems engineering effort
• Reuse of an artifact should reduce the expected systems
engineering effort for the development of a new system
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University of Southern California
Center for Systems and Software Engineering
Guidance for COSYSMO 2.0
• COSYSMO introduced in 2005
– Successful, implemented by both academia and industry
• Not without its limitations
– Relies on a “built from scratch” assumption
– Lack of reuse estimation capability cited as a potential source of
error
– Need to develop reuse estimation capability for COSYSMO 2.0
Reuse
Considerations
Reuse
Observations
Revised Drivers
Literature Review
Industry Survey
COSYSMO 2.0
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University of Southern California
Center for Systems and Software Engineering
Reuse Literature Observations
1. Reuse is done for the purpose of economic benefit, intending to
shorten schedule, reduce cost, and/or increase performance.
2. Reuse is not free, upfront investment is required to understand
the technical opportunities and limitations.
3. Products, processes, and knowledge are all reusable artifacts.
4. Reuse needs to be planned from the conceptualization phase
of programs.
5. Reuse is as much of an organizational issue as it is a technical
one.
6. Reuse is knowledge that must be deliberately captured in order
to be beneficial.
7. The benefits of reuse are limited to closely related domains.
8. The benefits of reuse do not scale linearly
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University of Southern California
Center for Systems and Software Engineering
Reuse Survey Results
1. Requirements reuse is only performed occasionally, but
has the largest “benefit” associated with it.
2. Reuse occurs more frequently early in the life cycle
than later.
3. Cost savings is the most promoted benefit for reuse,
but benefits also exist in risk, schedule, and
performance.
4. The proposed five categories of reuse are reasonable
in characterizing systems engineering reuse.
5. Experienced personnel is a key factor for successful
reuse.
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University of Southern California
Center for Systems and Software Engineering
COSYSMO Operational Concept
# Requirements
# Interfaces
# Scenarios
# Algorithms
Size
Drivers
Effort
Multipliers
- Application factors
-8 factors
- Team factors
-6 factors
COSYSMO
Effort
Calibration
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University of Southern California
Center for Systems and Software Engineering
Proposed COSYSMO 2.0
Operational Concept
4+1 Reuse
Categories
# Requirements
# Interfaces
# Scenarios
# Algorithms
- Application factors
- 8 factors (+1)
- Team factors
- 6 factors (+1)
Size
Drivers
Effort
Multipliers
COSYSMO
2.0
Effort
Calibration
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University of Southern California
Center for Systems and Software Engineering
Proposed Size Driver Extensions
New: Artifacts that are
completely new
New 1.0
Modified
Adopted: Artifacts that are
incorporated unmodified,
also known as “black box”
reuse
Managed: Artifacts that are
incorporated unmodified
and untested
Deleted: Artifacts that are
removed from a system
Reuse weight
Modified: Artifacts that are
inherited, but are tailored
Adopted
Managed
Deleted
0
Reuse category
4 or 5 categories
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University of Southern California
Center for Systems and Software Engineering
Which Methodology Provides Better
Estimation Power?
Methodology A
Reuse Extensions
(4+1 categories)
Methodology B
Reuse Extensions
(4+1 categories)
+
Reuse Cost Drivers
(Revised set)
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University of Southern California
Center for Systems and Software Engineering
COSYSMO 2.0 Status
• Dissertation proposal approved in October 2008
– In data collection/model validation phase
– Aiming for COSYSMO 2.0 delivery in Spring 2010
• Determine model updates needed to account for reuse
– 4+1 Reuse Categories (Size Drivers)
– 4+1 Reuse Categories & Revised Cost Drivers
• Mining the COSYSMO calibration data set
– 58% of projects have some reuse data
– Data provided as percentage of number of E/N/D value for each
size driver
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University of Southern California
Center for Systems and Software Engineering
Reuse Process
• Objectives
– Prescriptive guidance
– Illustrates a way for an organization to think about reuse from a
larger perspective (strategy, organization, etc.)
– Helps an organization that wants to do reuse, establish a
foundation
• Improvements to the process
–
–
–
–
Is this the right sequence?
Are these the right steps?
What happens in each step?
Are there any other feedback loops?
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University of Southern California
Center for Systems and Software Engineering
Reuse Process
Identify reuse strategy
Identify reuse artifacts
Reuse
intangibles
Define classes of reuse
Size
drivers
Cost
drivers
Risk assessment
Document future reuse
opportunities
Populate reuse
repository
Will be discussed
in detail
University of Southern California
Center for Systems and Software Engineering
Reuse of SE Artifacts
• Survey results identified frequency of SE artifacts that
are reused
–
–
–
–
Requirements
Architecture/design models
Test data/procedures
Documentation/templates
• What are other SE artifacts that are reused?
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University of Southern California
Center for Systems and Software Engineering
Reuse Scenarios
• What are some example scenarios of reusing systems
engineering artifacts?
– Ex: Block II of a satellite program; many requirements already
defined, interfaces are known, test procedures exist.
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University of Southern California
Center for Systems and Software Engineering
Reuse in the Cost Drivers
• Previous research/discussion focused on reuse in the
size drivers
– 4+1 reuse categories, reuse continuum
– On-going research will provide additional insight on this issue
• What is the impact of reuse on the cost drivers?
– Survey revealed non-technical, personnel factors significantly
influenced success of reuse
• Potential
– Definition changes?
– Rating scale changes?
– Modified set of drivers?
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University of Southern California
Center for Systems and Software Engineering
Capturing Reuse in the Cost Drivers
Cost Driver
Reuse
Impact On?
Impact On
Reuse?
Application Factors
Requirements Understanding
Architecture Understanding
Level of Service Requirements
Migration Complexity
Technology Risk
Documentation to Match Life Cycle Needs
# and Diversity of Installations/Platforms
# of Recursive Levels in the Design
Team Factors
Stakeholder Team Cohesion
Personnel/Team Capability
Personnel Experience/Continuity
Process Capability
Multisite Coordination
Tool Support
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University of Southern California
Center for Systems and Software Engineering
Organizational Impacts of Reuse
• What do systems engineering departments need to do
differently in order to support “strategic” reuse?
– Survey indicated “strategic” reuse is much more successful and
effective than “ad hoc” reuse; reuse needs to be planned early in
the lifecycle
– What mechanisms enable/hinder reuse?
– How do SE departments handle strategic vs. ad hoc reuse?
– To what degree does either strategy affect the SE department?
– What feedback loops exist in the reuse process?
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University of Southern California
Center for Systems and Software Engineering
Next Steps
• COSYSMO 2.0 data collection
– Call for participation
• Expert survey
– Validate reuse size driver weights & cost driver
adjustments
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University of Southern California
Center for Systems and Software Engineering
Call for Participation
Background
The USC Center for Systems and Software Engineering (CSSE) and Lean Advancement Initiative (LAI) at MIT in
collaboration with the INCOSE Measurement Working Group have initiated the next phase of development of a Systems
Engineering Cost Model called COSYSMO. Since the first version of the model was completed in 2005, COSYSMO has
been widely accepted and adopted by over a dozen industrial and government organizations. To continually address the
needs of the user community, an incremental update to the model is currently underway. This update, called COSYSMO 2.0,
will improve the estimation power of the model by accounting for systems engineering reuse. To perform an industry
calibration, we are seeking industry data in the form of labor actuals on various types of systems engineering projects that
involved a significant amount of reuse.
Benefits
By providing data for this model your organization will:
• ensure that your particular application domain is addressed by COSYSMO 2.0
• learn to tailor and calibrate the updated model for their specific application domain
• enable the quantification of varying degrees of systems engineering reuse on project estimates
• be able to claim in CMMI reviews that your systems engineering cost estimates are based on calibrated industry models
Proven Methodology
COSYSMO (Constructive Systems Engineering Cost Model) employs a proven methodology developed for the COCOMO
(Constructive Cost Model), the most widely used software cost model in the world.
Proven Process
USC-CSSE and LAI at MIT have proven processes in place to ensure the confidentiality of the data with its Corporate
Affiliates and Consortium Members. Successful data protection has enabled it to attract the participation of several
organizations in this effort including Boeing, Raytheon, Northrop Grumman, Lockheed Martin, General Dynamics, SAIC, L-3
Communications, BAE Systems, and the US Air Force Space & Missile Systems Center.
Contact
Jared Fortune [fortune@usc.edu]
Ricardo Valerdi [rvalerdi@mit.edu]
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