1. CEN 4010 First Lecture January 10, 2005 CEN 4010 Introduction to Software Engineering Spring 2005 Instructor: Masoud Sadjadi http://www.cs.fiu.edu/~sadjadi/Classes/CEN-4010/

2. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 2 Acknowledgements  Dr. Peter Clarke  Dr. Betty Cheng  Dr. Bernd Bruegge  Dr. Allen Dutoit EvaluationOverview: Introduction SW Life Cycle

3. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 3 Agenda  Course Introduction  Initial Evaluation  Software Life Cycle EvaluationOverview: Introduction SW Life Cycle

4. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 4 Course Home Page  Web Page –http://www.cs.fiu.edu/~sadjadi/Classes/CEN-4010/http://www.cs.fiu.edu/~sadjadi/Classes/CEN-4010/  General Information: –Office Hours: ECS 212C, M/W 17:00 – 18:00 or by appointment.  Important Links: –Course SyllabusCourse Syllabus –ProjectProject –Class Schedule, Reading Assignments, and Lecture NotesClass Schedule, Reading Assignments, and Lecture Notes  Class Notices –Please read your textbook before coming to class. –Pay attention to the reading assignments. EvaluationOverview: Introduction SW Life Cycle Home Page SE Overview Course Outcome

5. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 5 Prerequisite and References  Prerequisite –COP 3530 - Data Structures –Familiarity with  At least two higher level languages  The foundations of computing  Required Text –Bernd Bruegge and Allen H Dutoit, “Object-Oriented Software Engineering: Using UML, Patterns, and Java.”  Other reading material –Class notes. EvaluationOverview: Introduction SW Life Cycle Home Page Syllabus Project SE Overview Course Outcome

6. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 6 Grading  Grading Policy –Class Attendance and Participation: 10%. –Homework: 20%. –Term Project: 30%. –Mid-Term Exam: 20%. –Final Exam: 20%.  Grading Standard –The grading scale is: A: 90 | A-:87 | B+:84 | B: 80 | B-:77 | C+:74 | C: 70 | C-:65 | D+:60 | D: 55 | D-:50. –Note that a C- is not a C.  Attendance –Attendance will be taken during each class meeting. EvaluationOverview: Introduction SW Life Cycle Home Page Syllabus Project SE Overview Course Outcome

7. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 7 Tentative Course Schedule Refer to the Course SyllabusCourse Syllabus EvaluationOverview: Introduction SW Life Cycle Home Page Syllabus Project SE Overview Course Outcome

8. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 8 Project Objective and Grading  Objective –The primary objective of the projects is to give you practice in applying the phases of the software development process to a "real" software project.  Grading Scheme –The grade for the projects is based on three deliverables and class presentations, representing 30% of the final grade. –Each student in a project team will be evaluated separately and may receive a different grade. EvaluationOverview: Introduction SW Life Cycle Home Page SE Overview Syllabus Project Course Outcome

9. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 9 Deliverables and Presentation EvaluationOverview: Introduction SW Life Cycle Home Page SE Overview Syllabus Project Course Outcome Deliverable 1Requirements Analysis Document (RAD) (5%) RAD Template 2/14 Due at the beginning of the class. Presentation 1A brief description of SRD. Details will follow. (5%) 5 mins presentation for each group member. 2/14 Deliverable 2Design Document (DD) (5%) SDD Template ODD Template 3/28 Due at the beginning of the class. Presentation 2A brief description of DD. Details will follow. (5%) 5 mins presentation for each group member. 3/28 Deliverable 3Software documentation consisting of: (5%)  Requirements Analysis Document,  Design Document,  Implementation i.e. code design, and  Test Cases  User's Guide  A CD with all project material. 4/18 Due at the beginning of the class. Presentation 3A brief description of the software system - (5%) requirements, design, implementation and test cases. 5 mins presentation for each group member. 4/18

10. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 10 Project and Team Selection  Selection of Project: –Each group is responsible for selecting a project. –Before starting work on the project you must come and see me during my office hours so that we can decide on the scope of your project. –Project selection should be finalized by the end of Week 2 (Wednesday, Jan. 19). This means you have to come and see me before Jan. 19. –If you have difficulty in selecting a project I will assist you.  Project Teams –Each team shall consist of 5 to 6 students. –Let us decide on team members. EvaluationOverview: Introduction SW Life Cycle Home Page SE Overview Syllabus Project Course Outcome

11. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 11 What is Software Engineering? (1)  Systematic approach for developing software  “Methods and techniques to develop and maintain quality software to solve problems.” [Pfleeger, 1990]  “Study of the principles and methodologies for developing and maintaining software systems.” [Zelkowitz, 1978]  “Software engineering is an engineering discipline which is concerned with all aspects of software production.” [Sommerville] EvaluationOverview: Introduction SW Life Cycle Home Page SE Overview Definition Course Outcome How to apply?

12. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 12 What is Software Engineering? (2)  “Practical application of scientific knowledge in the design and construction of computer programs and the associated documentation required to develop, operate, and maintain them.” [Boehm, 1976]  “Deals with establishment of sound engineering principles and methods in order to economically obtain software that is reliable and works on real machines.” [Bauer, 1972] EvaluationOverview: Introduction SW Life Cycle Home Page SE Overview Definition Course Outcome How to apply?

13. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 13 Questions Addressed by SE  How do we ensure the quality of the software that we produce?  How do we meet growing demand and still maintain budget control?  How do we avoid disastrous time delays? EvaluationOverview: Introduction SW Life Cycle Home Page SE Overview Definition Course Outcome How to apply?

14. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 14 Why apply SE to Systems?  Provide an understandable process for system development.  Develop systems and software that are maintainable and easily changed.  Develop robust software and system.  Allow the process of creating computing- based systems to be repeatable and manageable. EvaluationOverview: Introduction SW Life Cycle Home Page SE Overview Definition Course Outcome How to apply?

15. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 15 How can we apply SE?  Modeling  Problem-solving  Knowledge acquisition  Rationale-driven EvaluationOverview: Introduction SW Life Cycle Home Page SE Overview Definition Course Outcome How to apply?

16. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 16 Modeling  “A model is an abstract representation of a system that enables us to answer questions about the system.”  Why use a model? –Systems are too large, too small, too complicated, or too expensive, to experience firsthand.  Models allow –Visualization –Comprehension EvaluationOverview: Introduction SW Life Cycle Home Page SE Overview Definition Course Outcome How to apply?

17. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 17 Problem Solving  Steps in problem solving: –Formulate the problem –Analyze the problem –Search for solutions –Decide on the appropriate solution –Specify the solution EvaluationOverview: Introduction SW Life Cycle Home Page SE Overview Definition Course Outcome How to apply?

18. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 18 Knowledge Acquisition  Domain specific knowledge.  New knowledge can affect the development process.  Knowledge acquisition is nonlinear – affects several of the software development models.  Risk assessment is important. EvaluationOverview: Introduction SW Life Cycle Home Page SE Overview Definition Course Outcome How to apply?

19. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 19 Rationale Management  Assumptions made about systems change constantly.  Application domain models stabilize, solution domain models are in constant flux. –Changes to the solution models due to:  design and implementation faults  new technology  Need to understand the context in which each design decision was made. EvaluationOverview: Introduction SW Life Cycle Home Page SE Overview Definition Course Outcome How to apply?

20. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 20 Course Outcomes  Familiarity with the Software Development Life Cycle.  Mastering the techniques to gather and specify the requirements of a medium-size software system using UML.  Mastering the techniques to design and implement a medium-size software system.  Familiarity with software testing techniques.  Familiarity with software documentation.  Familiarity with working in a small software development team.  Familiarity with system walkthroughs.  Familiarity with maintaining software and managing change. EvaluationOverview: Introduction SW Life Cycle Home Page SE Overview Course Outcome

21. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 21 Initial Evaluation  Background Survey –To get familiar with your interests in the course. –To understand what topics should be covered. –To get familiar with your research interests.  Initial Assessment –No grading value. –To assess the initial level of your knowledge. –To teach the course at an acceptable level. –To help you fulfill the course requirements. EvaluationOverview: Introduction SW Life Cycle

22. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 22 Agenda  Course Introduction  Initial Evaluation  Software Life Cycle EvaluationOverview: Introduction SW Life Cycle

23. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 23 Our Intention Requirements Software EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity

24. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 24 Our plan of attack Requirements Analysis Design Implementation Testing Delivery and Installation EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity

25. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 25 How it often goes Requirements Analysis D E L A Y Vaporware EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity

26. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 26 Inherent Problems  Requirements are complex –The client does not know the functional requirements in advance.  Requirements may be changing –Technology enablers introduce new possibilities to deal with nonfunctional requirements.  Frequent changes are difficult to manage –Identifying milestones and cost estimation are difficult.  There is more than one software system –Backward compatible with existing systems  Let’s view these problems as the nonfunctional requirements for a system that supports software development! –This leads us to software life cycle modeling EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity

27. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 27 Terminology (1)  participants – all persons involved in a project. e.g., developers, project manager, client, end users.  role – associated with a set of tasks assigned to a participant.  system – underlying reality.  model – abstraction of the reality.  work product – an artifact produced during development.  deliverable – work product for client. EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity

28. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 28 Terminology (2)  activity – a set of tasks performed toward a specific purpose.  milestone – end-point of a software process activity.  task – an atomic unit of work that can be managed and that consumes resources.  goal – high-level principle used to guide the project.  functional requirement – an area of functionality that the system must have. EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity

29. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 29 Terminology (3)  nonfunctional requirement – a constraint on the system.  notation – is a graphical or textual set of rules representing a model (e.g., UML)  method – a repeatable technique for solving a specific problem e.g. sorting algorithm  methodology – a collection of methods for solving a class of problems (e.g., Unified Software Development Process). EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity

30. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 30 Software Processes 1. Specification –requirements elicitation and analysis. 2. Development –systems design, detailed design (OO design), implementation. 3. Validation –validating system against requirements (testing). 4. Evolution –meet changing customer needs and error correction (maintenance). EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity

31. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 31 1. Software Specification (1)  Functionality of the software and constraints (non-functional requirements) on its operation must be defined.  Involves: –Requirements elicitation –The client and developers define the purpose of the system. –Output is a description of the system in terms of actors and uses cases. –Actors include roles such as end users and other computers the system needs. EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity Specification Development Validation Evolution

32. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 32 1. Software Specification (2)  Uses cases are general sequences of events that describe all possible actions between actor and the system for a given piece of functionality. Analysis  Objective: produce a model of the system that is correct, complete, consistent, unambiguous, realistic, and verifiable.  Developers transform the use cases into an object model that completely describes the system.  Model is checked for ambiguities and inconsistencies.  Output: Object model annotated with attributes, operations, and associations. EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity Specification Development Evolution Validation

33. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 33 2. Software Development (1)  Producing the software that meets the specification. System Design  Goals of the project are defined.  System decomposed into smaller subsystems (architectural model).  Strategies to build system identified –HW and SW platform, data management, control flow, and security.  Output: model describing subsystem decomposition and system strategies. EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity Specification Development Evolution Validation

34. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 34 2. Software Development (2) Object Design  Bridges the gap between analysis model and the strategies identified in the system design. Includes: –Describing object and subsystem interfaces –Selecting off–the-shelf components –Restructure object model to attain design goals  e.g., extensibility, understandability, and required performance.  Output: detailed object model annotated with constraints and supporting documentation. Implementation  Translation of the object model into source code.  No general process followed.  There are tools to assists the programmer such as CASE tools. EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity Specification Development Evolution Validation

35. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 35 Software Development Activities Problem Domain Implementation Domain Requirements Analysis What is the problem? System Design What is the solution? Object Design What is the solution in a specific context? Implementation How is the solution constructed? EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity Specification Development Evolution Validation

36. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 36 3. Software Validation (1)  Ensures the software does what the customer want.  The software conforms to its specification and meets the expectations of the customer. Validation: ‘Are we building the right product?’ Ensures the software meets the expectations of the customer. Verification: ‘Are we building the product right?’ Ensures the software conforms to the specification. EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity Specification Development Validation Evolution

37. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 37 3. Software Validation (2)  Techniques –Software inspections (static):  Analyze and check system representations (e.g., requirements documents, design diagrams, and program source code). –Software testing (dynamic):  Executing an implementation of the software with test data and examining the outputs against expected results.  V&V process establishes the existence of defects.  Debugging is a process that locates and corrects these defects. EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity Specification Development Evolution Validation

38. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 38 4. Software Evolution  Software must evolve to meet the customer needs.  Software maintenance is the process of changing a system after it has been delivered.  Reasons for maintenance –To repair faults. –To adapt the software to a different operating environment. –To add to or modify system’s functionality. EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity Specification Development Evolution Validation

39. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 39 Attributes of Good Software  Maintainability –Ease of changing the software to meets the changing needs of the customer.  Dependability –Reliability, security and safety.  Efficiency –Responsiveness, processing time, and memory usage.  Usability –Appropriate user interface and adequate documentation. EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity Specification Development Evolution Validation

40. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 40 Software Life Cycle  Software life cycle modeling –Attempt to deal with complexity and change.  Software life cycle –Set of activities and their relationships to each other to support the development of a software system.  Software development methodology –A collection of techniques for building models, which are applied across the software lifecycle. EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity

41. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 41 Software Life Cycle  Software construction goes through a progression of states Development Post- Development Pre- Development EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity Conception Childhood Adulthood Retirement

42. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 42 Software Life Cycle Models  Waterfall model and its problems –Pure Waterfall Model –V-Model  Iterative process models –Boehm’s Spiral Model –Unified Process Model  Entity-based models –Issue-based Development Model –Concurrent Development EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity Waterfall Iterative Entity-Based

43. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 43 Waterfall Model (1)  The waterfall model –First described by Royce in 1970  There seem to be at least as many versions as there are authorities - perhaps more Requirements Definition System and software design Implementation and unit testing Integration and system testing Operation and maintenance EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity Waterfall Iterative Entity-Based

44. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 44 Waterfall Model (2)  One or more documents are produced after each phase and “signed off”.  Points to note: –“Water does not flow up”.  it is difficult to change artifact produced in the previous phase. –This model should be used only when the requirements are well understood. –Reflects engineering practice. –Simple management model. EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity Waterfall Iterative Entity-Based

45. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 45 From Waterfall to V Model  Horizontal lines denote the information flow between activities at the same abstraction level. Requirements Specification System design Detailed Design Implementation Unit Test System and integration test Acceptance test EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity Waterfall Iterative Entity-Based

46. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 46 V Model  Similar to pure waterfall model but makes explicit the dependency between development and verification activities.  The left half of the V represents development and the right half system validation.  Note the requirements specification includes requirements elicitation and analysis. EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity Waterfall Iterative Entity-Based

47. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 47 Spiral Model (1)  Basic Idea –develop initial implementation, expose it to user, and refine it until an adequate system is produced.  Two types: –Exploratory –Throw-away prototyping  Advantages –model used when problem is not clearly defined.  Disadvantages –Process not visible, systems are poorly constructed, may require special tools and techniques. EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity Waterfall Iterative Entity-Based

48. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 48 Spiral Model (2) Requirements plan Concept of operation Risk analysis Prototype 1 Prototype 2 Prototype 3 Risk analysis Risk analysis S/w Reqs. Validation Development Plan Integration Plan Design Validation Acceptance Test Sys. Product Design Integration & Test Unit Test Code Detailed Design Design objectives, alternatives, and constraints Plan next phase Evaluate alternatives, identify and resolve risks Develop and verify next level product Not shown in detail EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity Waterfall Iterative Entity-Based

49. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 49 Spiral Model (3)  Tries to accommodate infrequent change during development.  Each round of the spiral involves: –Determine objectives –Specify constraints –Generate alternatives –Identify risks –Resolve risks –Develop and verify next level product –Plan EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity Waterfall Iterative Entity-Based

50. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 50 Incremental Development (1)  Mills et al. 1980 Define outline requirements Assign requirements to increments Design system architecture Develop system increment Validate increment Integrate increment Validate system System incomplete Final system EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity Waterfall Iterative Entity-Based

51. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 51 Incremental Development (2)  Software specification, design and implementation is broken down into a series of increments which are developed in turn.  Gives customers some opportunities to delay decisions on the detailed requirements of the system.  Services are identified and a priority allocated.  Each increment provides a subset of the system’s functionality. EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity Waterfall Iterative Entity-Based

52. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 52 Incremental Development (3) Advantages: –Customers do not have to wait for the entire system. –Customers gain experience using early increments of the system. –Lowers the risk of overall project failure. –Most important system services receives the most testing. Disadvantages: –May be difficult to map meaningful functionality into small increments. EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity Waterfall Iterative Entity-Based

53. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 53 Extreme Programming  The incremental approach has evolved to ‘extreme programming’ (Beck 1988).  Extreme programming: –Development and delivery of very small increments. –Customer involvement in the process. –Constant code improvement. –Egoless programming  Programs are regarded as group property! EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity Waterfall Iterative Entity-Based

54. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 54 Unified Software Development Process (1)  Similar to Boehm’s spiral model.  A project consists of several cycles, each ends with the delivery of a product to the customer.  Each cycle consists of four phases: –Inception –Elaboration –Construction –Transition  Each phase consists of a number of iterations. EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity Waterfall Iterative Entity-Based

55. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 55 Unified Software Development Process (2)  Inception ends with –commitment from the project sponsor to go ahead.  Elaboration ends with –basic architecture of the system in place, –a plan for construction agreed, –all significant risks identified, and –major risks understood enough not to be too worried.  Construction ends with –a beta-release system.  Transition –is the process of introducing the system to it users. EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity Waterfall Iterative Entity-Based

56. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 56 Unified Software Development Process (2) Analysis model Use case model Design model Deployment model Implementation model Test model specified by realized by distributed by verified by implemented by Requirements captured as a set of use cases. System Development EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity Waterfall Iterative Entity-Based

57. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 57 Unified Software Development Process (3)  Deployment model –physical communication links between hardware items. –relationships between physical machines and processes.  The models in the Unified Process are traceable –A model element can be traced to at least one element in an associated model.  Transition between models are seamless –we can tell in a foreseeable way how to get from an element in one model to one/more elements in an associated model. EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity Waterfall Iterative Entity-Based

58. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 58 Issue-Based Development  A system is described as a collection of issues –Issues are either closed or open. –Closed issues have a resolution. –Closed issues can be reopened (Iteration!).  The set of closed issues is the basis of the system model I1:Open I2:Closed I3:Closed A.I1:Open A.I2:Open SD.I1:Closed SD.I2:Closed SD.I3:Closed PlanningRequirements Analysis System Design EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity Waterfall Iterative Entity-Based

59. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 59 What to Choose?  PT = Project Time, MTBC = Mean Time Between Change  Change rarely occurs (MTBC >> PT): –Waterfall Model –All issues in one phase are closed before proceeding to the next phase  Change occurs sometimes (MTBC = PT): –Boehm’s Spiral Model –Change occurring during a phase might lead to an iteration of a previous phase or cancellation of the project  “Change is constant” (MTBC << PT) –Issue-based Development (Concurrent Development Model) –Phases are never finished, they all run in parallel  Decision when to close an issue is up to management.  The set of closed issues form the basis for the system to be developed. EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity

60. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 60 IEEE 1074  Standard for Developing Life Cycle Processes  Describes the set of activities and processes that are mandatory for the development and maintenance of software.  Process is a set of activities that is performed towards a specific purpose.  Processes are grouped into higher abstractions called process groups. EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity

61. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 61 Software Processes Process GroupProcesses Project ManagementProject Initiation Project Management and Control Software Quality Management Pre-developmentConcept Exploration System Allocation DevelopmentRequirements Design Implementation Post-developmentInstallation Operation and Support Maintenance Retirement Integral ProcessesVerification and Validation Software Configuration Management Document Development Training EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity

62. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 62 Capability Maturity Model (CMM) 1. Initial Level –ad hoc, no feedback from user, black box. 2. Repeatable Level –Each project has a well-defined sw life cycle model. 3. Defined Level –A document sw life cycle model for all managerial and technical activities across the org. exists. 4. Managed Level –Metrics for activities and deliverables are defined. 5. Optimizing Level –Process allows feedback of information to change process itself. EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity

63. First Lecture on Jan. 10, 2005CEN 4010: Introduction to Software Engineering 63 State of the Software Industry in 1995  Maturity LevelFrequency 1. Initial 70% 2. Repeatable 15% 3. Defined < 10% 4. Managed < 5% 5. Optimizing < 1% Source: Royce, Project Management, P. 364 EvaluationOverview: Introduction SW Life Cycle Motivation Terminology SW Processes SW Life Cycle Cap. Maturity