Process Modeling CS 4320 Fall 2003

Process Difficulties SW not a production line Each project is different—even within the same company No universally accepted processes for SE Shelfware No Training Resistance (is not always futile)

Levels of Process (Humphrey) U – Universe (Life Cycles) W – Worldly (sequence of tasks and prereq) A – Atomic (enormously detailed) Can also be viewed as: – Policies – Procedures – Standards

Example Levels (Humphrey) U – Waterfall Model W – Critical Design Review held before entry into implementation, Issues are submitted to… A – Actual checklist for critical design review

Levels of Process (Text) Meta-Object Facility – Model of Model Notation Process Metamodel – Model Notation (UML) Process Model – Model itself (RUP) Performing Process – What we actually do

Process Decomposition (ISO 12207) Process (High Level Category) Activity (Major Common Categories) Task (Actual Work Tasks)

Examples Process: Software Requirements Analysis Activity: Complete Requirements Spec Task: Conduct Requirements Review

Primary – Acquisition (Let the contract) – Supply (Fulfill the contract) – Development (Make the product) – Operation (Operate the product in a system) – Maintenance (Correct/Modify the product) ISO Std 12207

Organizational Processes – Management – Infrastructure – Improvement – Human Resource – Asset Management – Reuse Program Management – Domain Engineering

Supporting – Documentation – Configuration Management – Quality Assurance – Verification – Validation – Joint Review – Audit – Problem Resolution – Usability – Product Evaluation ISO Std 12207

Development Activities – Process Implementation – System Requirements Analysis – System Architectural Design – Software Requirements Analysis – Software Architectural Design – Software Detailed Design – Software Coding and Testing – Software Integration – Software Qualification Testing – System Integration – System Qualification Testing – Software Installation – Software Acceptance Support ISO Std 12207

U Level Software Life Cycle Models Examples of Models: – Code-and-Fix – Waterfall – Incremental, Design to Sched – Spiral – Evolutionary Proto, Delivery Life-cycle: A project-specific, sequenced mapping of activities. May be a “standard” model adapted for your specific project. Choose Right One for project and Tailor it Table 7-1 (Rapid Development) Choosing a life cycle model

Issues in Selecting Life Cycle How well are requirements understood? How “firm” are requirements? How long can you go without “something”? How much risk is there? How hard is it to use the model? How much overhead is required? Do I have an artificial schedule?

Process Architecture (ETVX) Entry Process Name Exit InputOutput Feedback Out Feedback In Measures Resources Needed Activity List N Interfaces

Filled out cell Marketing Inputs Project Planning Concept Approval 1. Approved SDP 2. Approved WBS 3. Project Init in MS Requests for Clarification Scope Changes Resource Schedule Info 1.Estimate Effort 2.Prepare WBS 3.Prepare Schedule 001 MS Project Interface: phone formal memo Interface: Approved ECP Measurement: Person-Months KLOC

Class Exercise, Process Models Pick a Life Cycle Model……. And let’s model it…

The Infosys Process Description 1. Overview 2. Participants 3. Entry Criteria 4. Exit Criteria 5. Inputs 6. Activities 7. Exit Criteria 8. Outputs 9. Measurements 10. Special Considerations 11. References