PSU CS 106 Computing Fundamentals II Product Life Cycle & SW Product Life Cycle HM 9/3/2007

2 © Dr. Herbert G. Mayer Agenda Definition: Product Life Cycle Generic PLC Phases (4) SW PLC Phases (6) Time Line of PLC Summary of PLC Phases

3 © Dr. Herbert G. Mayer Definition: Product Life Cycle The Product life cycle (PLC) describes a framework by which an organization manages the development of its products from inception to EOL

4 © Dr. Herbert G. Mayer Generic PLC Phases (4) 1.Exploration 2.Planning 3.Development 4.Refresh (or Deployment 1 st time) PLC phases progress sequentially. Due to feedback from learning in some later phases, earlier phases experience corrections or completions; also, for relatively short periods, some phases overlap. The 4 phases of the generic PLC are:

5 © Dr. Herbert G. Mayer SW PLC Phases (6) 1.Requirements Gathering 2.Requirements Specification 3.Architecture Design 4.Detailed Design 5.Implementation 6.Validation and Verification The more specific PLC for SW products refines the Exploration into a more elaborate requirements gathering and specification effort. Similarly, the Planning phase is broken into a High-level (architectural) and Detailed Design phase. The 6 phases of the generic PLC are:

6 © Dr. Herbert G. Mayer Time Line of PLC Exploration Planning Refresh Development Product Production Candidate (PPC) Product Qualified (PLQ) Product Post Mortem Product Architecture Document (PAD) Product Deployment Opportunity Assessment (OA) Opportunity To Product Map (OPM) Product Qual Approval (PQA) Product Launch Approval (PLA) Opportunity Feasibility Approval Opportunity Scope Approval Opportunity Commit Approval Product Commit Approval (PCA) Product Feasibility Approval (PFA) Product Scope Approval (PSA) Product Integration Exit Product Integration ReadyProduct Design Complete Opportunity Identification Approval

7 © Dr. Herbert G. Mayer Summary of PLC Phases ExplorationExploration PlanningPlanning RefreshRefresh DevelopmentDevelopment Exploration Phase analyzes market, business and technology trends & opportunities which identify product solutions, that are implementable and of evident added value. Planning Phase formalizes next level of detail including market requirements, decision times, product scope, usage, features, technology integration, and results in an approved, documented POR. Development Phase implements requirements defined in Planning Phase; its Milestones are synchronization points to quantify progress toward goal. Refresh Phase constitutes further product revisions (or EOL) after initial product launch; may include updates to software, hardware, and other technologies.

8 © Dr. Herbert G. Mayer Requirements During Exploration phase of PLC, the customer’s requirements are gathered Requirements define what needs to be done, not how it can be implemented Takes ~ 20% of total time, calendar time Error-prone, when not communicating with real customer –Experts need to contribute –Not just pointy-haired managers Requirements must be specified in written documents Documented requirements are signed off –Iterations of refinement –Forming an agreement Change Control process defines, whether how requirements can be changed before EOL

9 © Dr. Herbert G. Mayer Design During Planning phase of PLC, the product is designed Solution to requirements are designed in 2 phases Takes ~ 25% of total time, calendar time High-level (AKA architectural) design selects general, high- level methods –Including top-down approach –Or bottom-up approach selection Detailed design breaks architecture into small, implementable modules –With inputs, outputs, globals, parameters –Dependencies between modules –Ideal to have few dependencies Detailed design results in actual plans, with milestones, measurable goals, bottle-necks, and recovery plans Result is an agreed Plan of Record (POR)

10 © Dr. Herbert G. Mayer Implementation During Development phase of PLC, the detailed design documented in the POR is implemented I.e. the steps of the detailed design are actually executed –Sequentially to use experience of programmer –In parallel, to meet milestones on time Takes ~ 35% of total time, calendar time Can create large work force, progressing in parallel Milestones needs to be tracked, met, and if missed, a backup plan needs to be selected to meet final goal

11 © Dr. Herbert G. Mayer V&V and Refresh During Refresh phase of PLC, the implemented product is tested –If first release, run all Validation and Verification steps –If subsequent release, focus on new features Important to schedule some of V&V steps from day 1 –Possible to test modules via Unit Testing –Other parts tested via simulation –Rest desk-tested, or inspected Takes ~ 25% of total time, calendar time –Total of all phases not = 100% Critical to have devised automated tools for testing