1. ICM-Sw Essentials for 577 Process models Success models Product models
Planning and control
Milestone content
Process models
Life cycle
Anchor Points;
Risk management
Key practices
Success models
Business case
IKIWISI
Stakeholder win-win
Product models
Evaluation
and analysis
Process entry/exit
criteria
Product
Domain models;
Requirements;
Architecture;
Code;
Documentation
Property models
Cost
Schedule
Performance
Reliability …

2. Original Spiral and Misinterpretations?
Common Misinterpretations
Hack some prototypes
Fit spiral into waterfall
Incremental waterfalls
Suppress risk analysis
No concurrency, feedback
One-size-fits-all model
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3. “Spiral Development” Definition
A risk-driven process model generator
Used to guide concurrent engineering
Two distinguishing features:
Cyclic approach for growing system definition
Anchor point stakeholder-commitment milestones
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4. Six Spiral and ICM Model Essentials
1. Concurrent determination of artifacts in each cycle
2. Each cycle addresses objectives, constraints, alternatives, risks, artifact elaboration, stakeholders’ commitment
3. Risk-driven activity level of effort
4. Risk-driven artifact degree of detail
5. Managing stakeholder commitments via anchor-point milestones
6. Emphasis on system and life-cycle issues - vs. software and development issues
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5. Incremental Commitment Models
The Incremental Commitment Models (ICMs) for System Life Cycle Processes
For Systems (Human, Hardware and Software)
ICM for Software Intensive Systems (ubiquitous hardware)
ICM for Software (only) Systems
ICMs solve Spiral Model problems
Use spiral principles vs. diagram
Relate to stakeholder commitments and values: Make concurrency explicit
Use risk to explicitly show go-backs and skips
Provide view for handling mini-spirals
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6. Incremental Commitment Model for Sw Systems
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7. ICM Showing Software in Systems
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8. ICM for Software
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9. Software System Life Cycle Anchor Points
Common System/Software stakeholder commitment points
Defined in concert with Government, industry affiliates
Coordinated with the Rational Unified Process
Valuation Commitment Review (VCR)
Stakeholders’ commitment to support Inception (IRR)
Like getting going steady
Foundations Commitment Review [Life Cycle Objectives (LCO)]
Stakeholders’ commitment to support architecting (FCR)
Like getting engaged
Development Commitment Review (DCR) [LC Arch. (LCA)]
Stakeholders’ commitment to support full life cycle (through Transition)
Like getting married (Construction) and having first child (Transition)
Operation (post IOC/TRR and PRR)
Stakeholders’ commitment to support operations
Like raising a family
The anchor point milestones were defined in a pair of USC Center for Software Engineering Affiliates’ workshops, originally for the purpose of defining a set of common reference points for COCOMO II cost model estimates of spiral model projects’ cost and schedule. One of the Affiliates, Rational, Inc., had been defining the phases of its Rational Unified Process, and adopted the anchor point milestones as its phase gates.
The first two anchor points are the Life Cycle Objectives (LCO) and Life Cycle Architecture (LCA). At each of these anchor points the key stakeholders review six artifacts: operational concept description, prototyping results, requirements description, architecture description, life cycle plan, and feasibility rationale (see next chart for details).
The feasibility rationale covers the key pass/fail question: “If I build this product using the specified architecture and processes, will it support the operational concept, realize the prototyping results, satisfy the requirements, and finish within the budgets and schedules in the plan?” If not, the package should be reworked.
The focus of the LCO review is to ensure that at least one architecture choice is viable from a business perspective. The focus of the LCA review is to commit to a single detailed definition of the review artifacts. The project must have either eliminated all significant risks or put in place an acceptable risk-management plan.
The LCO milestone is the equivalent of getting engaged, and the LCA milestone is the equivalent of getting married. As in life, if you marry your architecture in haste, you and your stakeholders will repent at leisure. The third anchor point milestone, the Initial Operational Capability (IOC), constitutes an even larger commitment: It is the equivalent of having your first child.
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10. ICM-LeanMBASE/RUP Activity/Process Model
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11. MBASE Model Integration Framework
Process models
Life cycle anchor
points
Risk management
Key practices
Success models
Business case
IKIWISI
Stakeholder win-win
Property models
Cost
Schedule
Performance
Reliability
Product models
Domain model
Requirements
Architecture
Code
Documentation
Planning and control
Milestone content
Evaluation and
analysis
Process
entry/exit
criteria
Product
evaluation
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12. MBASE Invariants and Variants
1. Use of particular success, process, product, or property models.
  Choice of process or product representation.
3. Degree of detail of process, product, property, or success modeling.
4. Number of spiral cycles or builds between anchor points.
5. Mapping of activities onto Inception-Elaboration-Construction-Transition phases.
6. Mapping of staff levels onto activities.
    1. Defining and sustaining a stakeholder win-win relationship through the system's life-cycle.
2. Using the MBASE Model Integration Framework.
3. Using the MBASE Process Integration Framework.
4. Using the LCO, LCA, and IOC Anchor Point milestones.
5. Ensuring that the content of MBASE artifacts and activities is risk-driven.
Variants
Invariants
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13. IICM-Sw P3S Model Integration Process
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14. ICM-Sw*/MBASE**/Rational Anchor Point Milestones
App. Compos.
Inception
Elaboration, Construction
Transition
OCR /PRR
DCR/LCA
FCR/LCO
VCR
IOC=TRR
Stage Sys Devel Phase
Rqts.
Prod. Des.
Development
SRR
PDR
Elaboration Foundations
Inception Valuation
Construction
SAR
IOC
COCOMO II estimates
* Incremental Commitment Model for Sw ** MBASE: Model-Based (System) Architecting and Software Engineering
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15. COCOTS: Development Model
Time
LCO – Lifecycle Objectives
LCA – Lifecycle Architecture
IOC – Initial Operational Capability
COCOMO II Effort Estimate
COCOTS Effort Estimate
2. COTS Tailoring
1. COTS
Assessment
3. Glue Code
Development
4. System Effort due to COTS Volatility
New System Development Not Involving COTS Components
Staffing
FCR/LCO
(Requirements Review)
DCR/LCA
(PDR)
IOC
(SAR)
Elaboration
(RR)
Construction
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16. IICM-Sw P3S Models* – Integration
OCD
Shared Vision
System Capabilities
Key Stakeholders
System Boundary & Environment
Top-Level Business Case
Domain & Organization Description
Proposed System
Prototyping
Proj. Reqts.
Capability Reqts.
System Interface
Level of Service Reqts.
Evolution Reqts.
System Analysis
Architecture Design & Analysis
Implementation Design
Milestones and Products Responsibilities
Approach, Resources
FRD
Business Case
Reqts. Satisfaction
Process Rationale
Risk Assessment
Iteration Plan
Quality Plan
SSRD
LCP
SSAD
Iterations
Release Description
Test Plan
Test Results
Peer Review Report
Users Manual
CTS
* Not exhaustive
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17. Coverage/Traceability of MBASE Product Models to LCO
What about COCOMO?
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18. ICM-Sw/RUP Activity/Process Model
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19. Documentation Completeness
Inception
Elaboration
Construction
Transition
ECR
VCR
FCR/LCO
DCR/LCA
IOC/TRR
OCR/ PRR
Feasibility
Iterations
Architecture
Iterations
Usable
Iterations
Product
Releases
Management R E Q D S I M P R E Q D E S I M P D E P R E Q D E S I M P D E P R E Q D E S I M P D E P
Management
Management
Management
Versions of this chart are in the three main books on the Rational Unified Process (RUP) [Royce, 1998; Kruchten, 1998; and Jacobson, et al., 1999]. It shows the relations between LCO, LCA, and IOC milestones and the RUP Inception, Elaboration Construction, and Transition phases. It also illustrates that the requirements, design, implementation, and deployment artifacts are incrementally grown throughout the phases. As indicated in Variant 3b on Chart 11, the size of the shaded bars will vary from project to project.
RATIONAL
S o f t w a r e C o r p o r a t i o n
Artifact Key: REQ=requirements (OCD + SSRD); DES=design (SSAD + part FRD); IMP=implementation (CTS); DEP=deployment (CTS); Management = (LCP + part FRD) [Note: the size of the shaded bars varies from project to project – MBASE Variant 3b ]
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