Software Engineering: Overview of Selby/Boehm bookOutlineA Hegelian View of Software Engineering Evolution1950’s Thesis: Engineer Software Like HardwareThe SAGE Software Development Process - (Benington, 1956) “We were successful because we were all engineers”.1960’s Antithesis: Software Is Not Like Hardware - Four Brooks factors plus two1960’s Antithesis: Software Crafting1960’s Progress and Problems1970’s Antithesis: Formal and Waterfall ApproachesThe Royce Waterfall Model (1970) - Explicit feedback - “Do it twice”Increase in Software Cost-to-fix vs. Phase (1976)1970’s: Problems with Formal MethodsSlide 13Reuse and Object OrientationHP Product Line Reuse Investment and PayoffPeople: The Most Important Factor - SW engineering is of the people, by the people, and for the peopleDual 1990’s – Early 2000’s Antithesis: - Maturity Models and Agile MethodsAgile and Plan-Driven Home Grounds: Five Critical Decision FactorsCOTS: The Future Is HerePersistence of Legacy SystemsSlide 21People and Values:Software Engineering Is Of, By, and For the PeopleTheory W: Enterprise Success Theorem – And informal proofTheory W: WinWin Achievement TheoremInitial VBSE Theory: 4+1 - with Apurva JainInitial VBSE Theory: 4+1 Process – With a great deal of concurrency and backtrackingSlide 27EasyWinWin OnLine Negotiation StepsSlide 29Expectations Management: Unaffordable Response TimeEconomics (Chapters 2, 3)Slide 32Slide 33Slide 34Usual Hardware-Software Trend ComparisonSlide 36Software Productivity Trends - BernsteinROI of Systems EngineeringRESL Ratings for 161 Projects in the COCOMO DatabaseCOCOMO II RESL CalibrationEffect of Scale on ROIHow Much Architecting is Enough?Processes (Chapters 4, 6)The “Separation of Concerns” LegacyResulting Project Social StructureFrom the Spiral Model to the ICMLife Cycle Anchor PointsSlide 48Pass/Fail Feasibility RationalesSpiral Anchor Points Enable Concurrent EngineeringProcess Model PrinciplesThe Incremental Commitment Life Cycle Process: OverviewDifferent Risk Patterns Yield Different ProcessesICM HSI Levels of Activity for Complex SystemsRisk-Driven Scalable Spiral Model: Increment ViewSlide 56Process Principles in CrossTalk 2002 Top-5 Software ProjectsExample ICM HCI Application: Symbiq Medical Infusion Pump Winner of 2006 HFES Best New Design AwardSymbiq IV Pump ICM Process - ISymbiq IV Pump ICM Process - IIICM SummaryImplications for Funding, Contracting, Career PathsRisk Management (Chapters 5, 7)Is This A Risk?Slide 65Earlier, This Problem Was A RiskRisk Management Strategies: - Buying InformationOther Risk Management StrategiesTop-10 Risks: Software-Intensive Systems of Systems - CrossTalk, May 2004Average Change Processing Time: 2 Systems of SystemsEffect of Unvalidated Software SchedulesSlide 72Slide 73Supplier Integration: Rapid Adaptability to ChangeTop-10 Lists (Chapter 1)Top 10 Risk Items: 1989 and 1995The Top Ten Software Risk Items: 1995The Top Ten Software Risk Items (Concluded)Defect Reduction Top-10 ListSlide 80Slide 81Slide 82Slide 83The Future of Systems and SoftwarePareto 80-20 distribution of test case value [Bullock, 2000]Business Case for Value-Based TestingGlobalization: “The World is Flat” - Friedman, 2005What does a SISOS look like? - Network-Centric Air Traffic ControlIntegrated Enterprise ArchitecturesComputational Plenty: Process ImplicationsWild Cards: Autonomy and Bio-ComputingSlide 92Timeless Principles (+) and Aging Practices (-)Slide 94Slide 95Slide 96Future Challenges for SW Engineering Education - Student careers go through 2050’sUniversity of Southern CaliforniaCenter for Systems and Software EngineeringBarry Boehm, USCCS 510Fall [email protected]://csse.usc.eduSoftware Engineering:Overview of Selby/Boehm bookUniversity of Southern CaliforniaCenter for Systems and Software Engineering01/14/19 ©USC-CSSE 2Outline•What have we learned? (chapter 8)•Some book highlights–People and values (chapters 7, 9)–Economics (chapters 2, 3)–Processes (chapters 4, 6)–Risk Management (chapter 5)–Top-10 lists (chapter 1)•Where are we going? (chapter 10)University of Southern CaliforniaCenter for Systems and Software Engineering01/14/19 ©USC-CSSE 3A Hegelian View of Software Engineering EvolutionUniversity of Southern CaliforniaCenter for Systems and Software Engineering01/14/19 ©USC-CSSE 41950’s Thesis: Engineer Software Like Hardware•Hardware-oriented:–Software applications: airplanes, bridges, circuits–Economics: Boehm supervisor, 1955•“We’re paying $600/hour for that computer, and $2/hour for you, and I want you to act accordingly.”–Professional Societies: Association for Computing Machinery, IEEE Computer Society–Software Processes: SAGE (Semi-Automated Ground Environment)•1 MLOC air defense system, real-time, user-intensive•Successful development of highly unprecedented system•Hardware-oriented waterfall-type processUniversity of Southern CaliforniaCenter for Systems and Software Engineering01/14/19 ©USC-CSSE 5OPERATIONAL PLANMACHINE SPECIFICATIONS OPERATIONAL SPECIFICATIONSPROGRAM SPECIFICATIONSCODING SPECIFICATIONSCODINGPARAMETER TESTING (SPECIFICATIONS)ASSEMBLY TESTING (SPECIFICATIONS)SHAKEDOWNSYSTEM EVALUATIONThe SAGE Software Development Process - (Benington, 1956)“We were successful because we were all engineers”.University of Southern CaliforniaCenter for Systems and Software Engineering01/14/19 ©USC-CSSE 61960’s Antithesis: Software Is Not Like Hardware- Four Brooks factors plus two•Invisibility: like the Emperor’s Magic Cloth•Complexity: Royce, “for a $5M procurement, need a 30-page spec for hardware, and a 1500-page spec for software”•Conformity: executed by computers, not people•Changeability: up to a point, then becomes difficult•Doesn’t wear out: different reliability, maintenance phenomena•Unconstrained: can program antigravity, time travel, interpenetration, …University of Southern CaliforniaCenter for Systems and Software Engineering01/14/19 ©USC-CSSE 71960’s Antithesis: Software Crafting•Flexible materials, frequent changes as above•SW demand exceeded supply of engineers–Music, history, art majors–Counter culture: question authority–Cowboy programmers as heroes–Code-and-fix process–Hacker culture (Levy, 1984)•Collective code ownership•Free software, data, computing access•Judge programmers by the elegance of their codeUniversity of Southern CaliforniaCenter for Systems and Software