1. Requirements Analysis & Specification Requirements Analysis & Specification Conceptual/System Design Conceptual/System Design Detailed/Program Design Detailed/Program Design Implementation/Coding Implementation/Coding Unit & Integration Testing Unit & Integration Testing System Testing System Testing System Delivery System Delivery Maintenance Maintenance Software Development Stages

2. Why do Project Fail Unrealistic project goalsUnrealistic project goals Inaccurate estimates of needed resourcesInaccurate estimates of needed resources Ambiguous customer requirementsAmbiguous customer requirements Poor communication among developersPoor communication among developers Poor project managementPoor project management Change in technologyChange in technology Inappropriate team skillsInappropriate team skills Rapid change in technologyRapid change in technology

3. Software Quality MaintainabilityMaintainability Can evolve Can evolve DependabilityDependability Modifying part won’t affect the whole system Modifying part won’t affect the whole system EfficiencyEfficiency Speed, performance, reliability … etc Speed, performance, reliability … etc UsabilityUsability Easy to use and understand Easy to use and understand Re-usableRe-usable Concise and precise artifacts of a system Concise and precise artifacts of a system

4. Waterfall Model Waterfall Model V Model V Model Evolutionary Model Evolutionary Model Phased Development Model Phased Development Model Spiral Model Spiral Model Component-based Software Engineering (CBSE) Component-based Software Engineering (CBSE) Software Lifecycle Models

5. Waterfall Model

6. V Model

7. Evolutionary Model Iteration 1Iteration 3Iteration 2Iteration 4 Req/spec Design Code Test Req/spec Design Code Test Req/spec Design Code Test Req/spec Design Code Test New Req

8. Phased Development Model A. Tew 1999

9. Boehm’s Spiral Model PLAN DEVELOP AND TEST DETERMINE GOALS, ALTERNATIVES, CONSTRAINTS EVALUATE ALTERNATIVES AND RISKS Requirements, life-cycle plan Budget 1 Alternatives 1 Constraints 1 Risk analysis 1 2 3 4 Constraints 2 3 4 Budget 2 3 4 Alternatives 2 3 4 Prototype 1 Proto- type 2 Proto- type 3 Proto- type 4 Concept of operation Software requirements Validated requirements Development plan Integration and test plan Software design Validated, verified design Detailed design Code Unit test System test Acceptance test Implementation plan [Pfleeger 98] start

10. CBSD Model Req/spec Design Code Test Explore Available Components Select Components Assemble System Examine Component 1 2 12 34 2 1