Lesson2.pptx
- 2. Objectives: 1. Describe the standard development process in terms of capability maturity model for quality management and ten principles of system development 2. Identify and discuss the different process for developing information system. 3. Describe the PIECES framework for categorizing problems, opportunities and directives.
- 3. Objectives: 4. Identify and describe the phases of system development. 5. Discuss the different scheme for methodological strategies 6. Describe the various automated tools for systems development.
- 4. • System development process is a set of activities, methods, best practices, deliverables, and automated tools that stakeholders use to develop and maintain information systems and software. • System development process must be manage on a project- by-project basis. • Project manager is a stakeholder who accept the responsibility for ensuring that the system is developed on time, within the budget, and with acceptable quality.
- 5. • The activity of managing a project is referred to as project management. • Project management is the activity of defining, planning, directing, monitoring, and controlling a project to develop an acceptable system within the allotted time and budget. • The process of planning, scheduling, monitoring, controlling, and reporting upon the development of an information system. • Many organization adopt and follow standardized system development process to promote quality and in order to increase their competitive advantage.
- 6. • A consistent process create efficiencies that allow management to shift resources between projects. • A consistent methodology produces consistent documentation that reduces a lifetime costs to maintain the systems. • Some government (e.g U.S government) has mandated any organizations seeking to develop software for the government must adhere to certain quality management requirements.
- 8. Capability Maturity Model • Capability Maturity Model (CMM) a standardized framework for assessing the maturity level of an organization’s information systems development and management processes and products. It consists of levels of maturity. • Level 1 – Initial: This is sometimes called anarchy or chaos. At this level, system development projects no consistent process. Documentation is not consistent from one project to the next, thus creating problems for those who must maintain a system over its lifetime.
- 9. Capability Maturity Model • Level 2 – Repeatable: At this level, project management processes and practices are established to track project costs, schedules, and functionality. The focus is on project management. A system development process is always followed, but it may vary from project to project. • Level 3 – Defined: In this level, a standard system development process is purchased or developed. As a result of using a standardized process for all projects, each project results in consistent and high-quality documentation and deliverables. The process is stable, predictable, and repeatable.
- 10. Capability Maturity Model • Level 4 – Managed: In this level, measurable goals for quality and productivity are established. Detailed measures of the standard system development process and product quality are routinely collected and stored in a database. There is an effort to improve individual project management based on this collected data. Thus, management seeks to become more proactive than reactive to systems development problems. • Level 5 – Optimizing: In this level, the standardized system development process is continuously monitored and improved based on measures and data analysis established in Level 4. Lesson learned are shared across the organization, with special emphasis on eliminating inefficiencies in the system development process while sustaining quality.
- 11. Principles for System Development • Get the users involved • Use a problem-solving approach • Establish phases and activities • Document throughout development • Establish standards • Manage the process and projects • Justify information system as capital investment • Don’t be afraid to cancel or revise scope • Divide and conquer • Design system for growth change
- 12. A System Development Process System Development Process General Description System Initiation The initial planning for a project to define initial business scope, goals, schedule, and budget. System Analysis The study of a business problem domain to recommend improvements and specify the business requirements and priorities for the solution. System Design The specification or construction of technical, computer- based solution for the business requirements identified in a system analysis. System Implementation The construction, installation, testing, and delivery of a system into production.
- 13. • The motivation of most projects are combination of problems, opportunities, and directives. • Problem is an undesirable situation that prevents the organization from fully achieving its mission, vision, goals, and/ or objectives. • Opportunity is chance to improve the organization even in the absence of identified problem. • Directive is a new requirement that’s imposed by management, government, or some external influence.
- 14. The PIECES Problem- Solving Framework and Checklist • PIECES is a framework for classifying problems. It was developed by James Wetherbe. • The PIECES framework is equally suited to analyzing both manual and computerized systems and application.
- 15. The PIECES Problem- Solving Framework and Checklist PERFORMANCE • Throughput – the amount of work performed over some period of time. • Response time – the average delay between a transaction or request, and a response to that transaction. INFORMATION (and Data) • Outputs 1. Lack of any information 2. Lack of necessary information 3. Lack of relevant information
- 16. The PIECES Problem- Solving Framework and Checklist 4. Too much information – “information overload” 5. Information that is not in a useful format. 6. Information that is not accurate 7. Information that is difficult to produce 8. Information is not timely to its subsequently use •Inputs 1. Data is not captured 2. Data is not captured in time to be useful 3. Data is not accurately captured – contains error
- 17. The PIECES Problem- Solving Framework and Checklist 4. Data is difficult to capture 5. Data is captured redundantly – same data captured more than once 6. Too much data is captured. 7. Illegal data is captured 8. Stored Data 9. Data is stored redundantly in multiple files and/or databases 10.Same data items have different values in different files (poor data integration)
- 18. The PIECES Problem- Solving Framework and Checklist 11.Stored data is not accurate 12.Data is not secure to accident or vandalism 13.Data is not well-organized 14.Data is not flexible – not easy to meet new 15.Data is not accessible
- 19. The PIECES Problem- Solving Framework and Checklist • Stored Data 1. Data is stored redundantly in multiple files and/or databases 2. Same data items have different values in different files (poor data integration) 3. Stored data is not accurate 4. Data is not secure to accident or vandalism 5. Data is not well-organized 6. Data is not flexible – not easy to meet new 7. Data is not accessible
- 20. The PIECES Problem- Solving Framework and Checklist • ECONOMICS 1. Costs 2. Costs are unknown 3. Costs are untraceable to source 4. Costs are too high • Profits 1. New markets can be explored 2. Current marketing can be improved 3. Orders can be increased
- 21. The PIECES Problem- Solving Framework and Checklist • CONTROL 1. Too little security or control 2. Input data is not adequately edited 3. Crimes (e.g. fraud, embezzlement) are committed against data. 4. Ethics are breached on data and information – refers to data or information getting to unauthorized people. 5. Redundantly stored data is inconsistent in different files or databases.
- 22. The PIECES Problem- Solving Framework and Checklist 6. Data privacy regulations or guidelines are being violated. 7. Processing errors are occurring (either by people, machines, or software) 8. Decision making errors are occurring. • Too much control or security 1. Bureaucratic red tape slows the system 2. Controls inconvenience customers or employees 3. Excessive controls cause processing delays
- 23. The PIECES Problem- Solving Framework and Checklist • EFFICIENCY • People, machines or computers waste time 1. Data is redundantly input or copied. 2. Data is redundantly processed 3. Information is redundantly generated • People, machines, or computers waste material and supplies • Effort required for tasks is excessive
- 24. The PIECES Problem- Solving Framework and Checklist • SERVICE A. The system is produces inaccurate results B. The system produces inconsistent results C. The system produces unreliable results D. The system is not easy to learn E. The system is not easy to use F. The system is awkward to use G. The system is inflexible to new or exceptional situations H. The system is inflexible to change I. The system is incompatible with other systems
- 25. The System Development Phases • Scope Definition – scope defines how big we think the project is. It also triggered by some combination of problems, opportunities, and directives. • Problem Analysis studies the existing system and analyzes findings to provide the project team with a more thorough understanding of the problems triggered the project. • Requirement Analysis – defines and prioritize the business requirements. • Logical Design – translate business requirements into system model.
- 26. The System Development Phases • Decision Analysis phase – given business requirements and the logical system models there are usually numerous alternative ways to design a new information system to fulfill those requirements. • The purpose of decision analysis phase is to (1) identify candidate technical solutions, (2) analyze those candidate solutions for feasibility, and (3) recommend a candidate system as the target solution to be designed.
- 27. Criteria to Evaluate Design • Technical feasibility refers to the technical resources needed to develop, purchase, install, or operate the system. • Operational feasibility means that a proposed system will be used effectively after it has been developed. • Schedule feasibility means that a project can be implemented in an acceptable time frame. • Economic feasibility means that projected benefits of the proposed system outweigh the estimated costs usually considered the total cost, which includes ongoing support and maintenance costs, as well as an acquisition cost.
- 28. Criteria to Evaluate Design • Physical Design and Integration phase is transform the business requirements into physical specification that will guide system construction. • Construction and Testing – the purpose of is (1) to build and test a system that fulfills business requirements and physical design specifications (2) to implement the interfaces between the new system and existing systems. • Installation and delivery phase serves to deliver the system into operation • System operation and maintenance – system require ongoing support to remain of its useful and productive lifetime.
- 29. Activities involves in System development • Fact-finding is the formal process of using research, interviews, meetings, questionnaires, sampling, and other techniques to collect information about system problems, requirements, and preferences. It is also information gathering or data collection • Documentation and Presentation. Documentation is the ongoing activity of recording facts and specifications for a system for current and future reference. Presentation is the ongoing activity of communicating findings, recommendations, and documentation for review by interested users and managers. Presentation might be either written or verbal.
- 30. Activities involves in System development • Feasibility Analysis is the activity by which feasibility is measured and assessed. Feasibility measures include technical, operational, economic, schedule and risk feasibility. • Process and project management. Process management is an ongoing activity that that documents, teaches, oversees the use of, and improves an organization’s chosen methodology for systems development. It is also concerned with phases, activities, deliverables, and quality standards that should be consistently allied all projects. • Project management is the process of scoping, planning, staffing, organizing a project to develop an information system at minimum cost within a time frame, and with acceptable quality.
- 31. System Development Approach • Waterfall development approach is an approach to systems analysis and design that complete each phase one after another and only once. • Iterative development approach is an approach to systems analysis and design that completes the entire information system in successive iterations. Each iteration does some analysis, some design, and some construction. Synonyms include incremental and spiral. • Spiral model represents a series of iterations, or revisions, based on user feedback.
- 32. Phases of Waterfall Model
- 33. Phases of Waterfall Model 1. Systems Planning phase • The systems planning phase begins with a system request. • System request is a formal request to the IT department which describes problems or desired changes in an information system or business process. • A system request could come from the top manager, planning team, a department head, or the IT department itself.
- 34. Phases of Waterfall Model • The purpose of this phase is to perform preliminary investigation to evaluate an IT-related business opportunity or problem. • The preliminary investigation is a critical step because the outcome will affect the entire development process. • A key part of preliminary investigation is feasibility study that reviews anticipated costs and benefits and recommends a course of action based on operational, technical, economic, and time frame factors.
- 35. Phases of Waterfall Model 2. System Analysis • The purpose of the system analysis phase is to build a logical model of the new system. The first step is requirement modeling, where you investigate business processes and document what the new system must do to satisfy user. • The deliverable for the system analysis phase is the system requirements document. The system requirement document describes management and user requirements, costs and benefits, and outlines alternative development strategies.
- 36. Phases of Waterfall Model 3. System design • The purpose of the system and design phase is to create a physical model that will satisfy all documented requirements for the system. In this phase, the user interface and identity necessary outputs, inputs, and processes are design. • The deliverable for this phase is the system design specification, which is presented to management and users for review and approval.
- 37. Phases of Waterfall Model 4. System Implementation • In this phase, the new system is constructed. The objective of the system implementation phase is to deliver a completely functioning and documented information system • The system implementation phase also includes a systems evaluation. System evaluation is an assessment to determine whether the systems operate properly and if costs and benefits are within expectations.
- 38. Phases of Waterfall Model 5. System Support and Security • During the systems support and security phase, the IT staff maintains enhances, and protects the system. Maintenance changes correct errors and adapt changes in the environment. Enhancements provide new features and benefits. The objective during this phase is to maximize return on the IT investment. • Security controls safeguard the system from both the external and internal threats. A well designed system must be secure, reliable, maintainable, and scalable. A scalable design can expand to meet new business requirements and volumes.
- 39. Taxonomy or Classification Scheme for Methodological Strategies •Prescriptive touches all the bases or follow all the rules. •Adaptive changes as needed within certain guidelines. •Model-driven focus on the object oriented technologies being used to construct most of today’s system. •Product driven tend to emphasize either rapid prototyping or writing code as soon as possible.
- 40. Most Commonly Used Approach to Analyzing and designing Information System • System Modeling is a picture of a system that represents reality or desired reality. It is used to illustrate and communicate the knowledge, process, or interface building blocks of information systems. • Process Modeling is a process-centered technique popularized by the structured analysis and design methodology that used models of business process requirements to derive effective software designs for system. It was founded in the structured analysis and design methodologies.
- 41. Most Commonly Used Approach to Analyzing and designing Information System • Structured analysis introduced a modeling tool called data flow diagram to illustrate the flow of data through a series of business processes. • Object modeling is a technique that attempts to merge the data and process concerns into singular constructs called objects. Object models are the diagram that document a system in terms of its objects and their interactions.
- 42. Rapid Application Development Strategy • Rapid Application Development (RAD) is a system development strategy that emphasizes speed of development strategy that emphasizes speed of development through extensive user involvement in the rapid, iterative, and incremental construction of a series of functioning prototypes of a system that eventually evolves into a final system.
- 43. Rapid Application Development Strategy The Phases of the RAD Model 1. Requirements planning combines elements of the system planning and system analysis phases of the SDLC. 2. User Design users interact with systems analysts and develop models and prototypes that represent all system processes, outputs, and inputs. 3. Construction focuses on program and application development tasks similar to the SDLC. 4. Cutover resembles the final tasks in SDLC implementation phase, including data conversion, testing, changeover to the new system, and user training.
- 44. The Commercial Application Package Implementation Strategy •Commercial Application Package is a software application that can be purchased and customized to meet the business requirement of a large number of organizations or specific industry. A synonym is commercial off-the-shelf (COTS) system. •The ultimate commercial solution is Enterprise Resource Planning or ERP. ERP solutions provide all of the core information system application for entire business.
- 45. The Commercial Application Package Implementation Strategy •For example, an organization might purchase for a single business function such as accounting, human resources, or procurement. •The packaged must be selected, installed, customized, and integrated into the business and its other existing information systems.
- 46. Automated Tools • Computer –Assisted Systems Engineering (CASE) Tools is automated software tools that support the drawing and analysis of system models and associated specifications. Some CASE Tools also provide prototyping and code generation capabilities. • CASE repository is a system developer’s database where developers can store system models, detailed descriptors and specifications, and other products of systems development.
- 47. Automated Tools The following are the CASE facilities: 1. Diagramming tools are used to draw the systems models required or recommended in most system development methodologies. 2. Dictionary tools are used to record, delete, edit, and output detailed documentation and specifications. 3. Design tools can be used to develop mock-ups of system components such as inputs and outputs.
- 48. Automated Tools 4. Quality management tools analyze system models, descriptions and specifications, and design for completeness, consistency and conformance to accepted rules of the methodologies. 5. Documentation tools are used to assemble, organize, and report on systems models, descriptions and specifications, and prototypes that can be reviewed by system owners, users, designers, and builders. 6. Design and code generator tools automatically generate database designs and application programs or significant portions of those programs.
- 49. Automated Tools 7. Testing tools simulate transactions and data traffic, measure performance, and provide configuration management of tests plans and test scripts. 8. Application Development Environments (ADE) is an integrated software development tool that provides all the facilities necessary to develop new application software with maximum speed and quality. 9. Process and project Managers Application is an automated tool that helps to plan system development activities, estimate and assign resources, monitor progress against schedule and budget, control and modify schedule and resources and report project progress.