Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

تحليل النظم


Published on

Published in: Education, Technology, Business
  • Be the first to comment

  • Be the first to like this

تحليل النظم

  1. 1. 1. SYSTEMS ANALYSIS & DESIGN• feasibility study• general design• prototyping• detail design• functional specifications
  2. 2. 2. USER SIGN OFF• Signing in your system
  3. 3. 3. PROGRAMMING• design• coding• testing
  4. 4. 4. IMPLEMENTATION• training• conversion• installation
  5. 5. 5. USER ACCEPTANCE• The System Development CycleFrom information requirements to final implementation, the systemdevelopment cycle is an ongoing process.• As the business changes, information requirements change, and the cycle continues.
  6. 6. Project Time Line• In software engineering the SDLC conceptunderpins many kinds of softwaredevelopment methodologies.• These methodologies form the framework forplanning and controlling the creation of aninformation system:
  7. 7. The software development process.Systems development phases1 Initiation/planning2 Requirements gathering and analysis3 Design4 Build or coding5 Testing6 Operations and maintenanceSystems development life cycle topics1 Management and control2 Work breakdown structure organization3 Baselines in the SDLC4 Complementary to SDLCStrengths and weaknesses
  8. 8. Project Time LineOverview• Systems Development Life Cycle (SDLC) is a processused by a systems analyst to develop an informationsystem, includingrequirements, validation, training, and user(stakeholder) ownership. Any SDLC should result in ahigh quality system that meets or exceeds customerexpectations, reaches completion within time and costestimates, works effectively and efficiently in thecurrent and planned Information Technologyinfrastructure, and is inexpensive to maintain and cost-effective to enhance.
  9. 9. Project Time Line• In project management a project can bedefined both with a project life cycle (PLC) andan SDLC, during which slightly differentactivities occur.• According to Taylor (2004) "the project lifecycle encompasses all the activities of theproject, while the systems development lifecycle focuses on realizing the productrequirements”
  10. 10. Systems development phases• waterfall model: a sequence of stages in whichthe output of each stage becomes the inputfor the next.
  11. 11. Systems development phases• Initiation• System concept development• Planning• Requirements analysis• Design• Development• Integration and test• Implementation• Operation NS Maintenance• Disposition
  12. 12. SLDC
  13. 13. SLDC• The SDLC can be divided into ten phases during whichdefined IT work products are created or modified.• The tenth phase occurs when the system is disposed ofand the task performed is either eliminated ortransferred to other systems.• The tasks and work products for each phase aredescribed in subsequent chapters.• Not every project will require that the phases besequentially executed• The phases are interdependent.• Depending upon the size and complexity of the project,phases may be combined or may overlap.[7]
  14. 14. Initiation/planning• To generate a high-level view of the intended projectand determine the goals of the project. The feasibilitystudy is sometimes used to present the project toupper management in an attempt to gain funding.• Projects are typically evaluated in three areas offeasibility: economical, operational or organizational,and technical.• It is also used as a reference to keep the project ontrack and to evaluate the progress of the MIS team.• The MIS is also a complement of those phases.• This phase is also called as analysis phase....
  15. 15. Requirements gathering and analysis• The goal of systems analysis is to determinewhere the problem is in an attempt to fix thesystem.• This step involves "breaking down" the system indifferent pieces to analyze the situation,analyzing project goals, "breaking down" whatneeds to be created and attempting to engageusers so that definite requirements can bedefined (Decomposition computer science).• Requirements Gathering sometimes requiresindividuals/teams from client as well as serviceprovider sides to get detailed and accurate
  16. 16. Design• In systems, design functions and operationsare described in detail, including screenlayouts, business rules, process diagrams andother documentation. The output of this stagewill describe the new system as a collection ofmodules or subsystems.
  17. 17. Design• The design stage takes as its initial input therequirements identified in the approvedrequirements document.• For each requirement, a set of one or moredesign elements will be produced as a resultof interviews, workshops, and/or prototypeefforts.
  18. 18. Design• Design elements describe the desiredsoftware features in detail, and generallyinclude functional hierarchy diagrams, screenlayout diagrams, tables of businessrules, business processdiagrams, pseudocode, and a complete entity-relationship diagram with a full datadictionary.• These design elements are intended todescribe the software in sufficient detail thatskilled programmers may develop the
  19. 19. Build or coding• Modular and subsystem programming codewill be accomplished during this stage.• Unit testing and module testing are done inthis stage by the developers.• This stage is intermingled with the next in thatindividual modules will need testing beforeintegration to the main project.
  20. 20. Testing• The code is tested at various levels in softwaretesting. Unit, system and user acceptancetesting are often performed.
  21. 21. TestingSome Iteration occur at this stage.Below are the following types of testing:• Data set testing.• Unit testing• System testing• Integration testing• Black box testing• White box testing• Regression testing• Automation testing• User acceptance testing• Performance testing
  22. 22. Operations and maintenance• The deployment of the system includeschanges and enhancements before thedecommissioning or sunset of the system.• Maintaining the system is an important aspectof SDLC.• As key personnel change positions in theorganization, new changes will beimplemented, which will require systemupdates.
  23. 23. Systems development life cycle topics• Management and control
  24. 24. SDLC Phases Related to ManagementControls.• The Systems Development Life Cycle (SDLC)phases serve as a programmatic guide toproject activity and provide a flexible butconsistent way to conduct projects to a depthmatching the scope of the project.
  25. 25. Work Breakdown Structure• To manage and control any SDLC initiative, eachproject will be required to establish some degreeof a Work Breakdown Structure (WBS) to captureand schedule the work necessary to complete theproject.• The WBS and all programmatic material is in the“Project Description” section of the projectnotebook.• The WBS format is mostly left to the projectmanager to establish in a way that best describesthe project work.• There are some key areas that must be defined inthe WBS as part of the SDLC policy.
  26. 26. Work breakdown structureorganizationThe following diagram describes three key areasthat will be addressed in the WBS in a mannerestablished by the project manager
  27. 27. Work Breakdown Structure• The upper section of the Work BreakdownStructure (WBS) should identify the majorphases and milestones of the project in asummary fashion.• The upper section should provide an overviewof the full scope and timeline of the projectand will be part of the initial projectdescription effort leading to project approval.• The middle section of the WBS is based on theseven Systems Development Life Cycle (SDLC)phases as a guide for WBS task development.
  28. 28. Work Breakdown Structure• The WBS elements should consist ofmilestones and “tasks” as opposed to“activities” and have a definitive period(usually two weeks or more). Each task musthave a measurable output (e.g. document,decision, or analysis).
  29. 29. Work Breakdown Structure• A WBS task may rely on one or more activities(e.g. software engineering, systemsengineering) and may require closecoordination with other tasks, either internalor external to the project.
  30. 30. Work Breakdown Structure• Any part of the projectneeding support fromcontractors should have aStatement of work (SOW)written to include theappropriate tasks from theSDLC phases.• The development of a SOWdoes not occur during aspecific phase of SDLC but isdeveloped to include thework from the SDLC processthat may be conducted byexternal resources such ascontractors.[9]
  31. 31. Understand what a SOW is.Know what to include.• Major deliverables and when theyre expected.• The tasks that support the deliverables, as well aswhich side -- the hiring company or the serviceprovider -- will perform those tasks.• The projects governance process, along with howoften governing committees will meet.• What resources are required for the project, whatfacilities will be used and whose equipment will beneeded, as well as testing requirements.• Who will pay which costs and when.• "The statement of work pulls together all the elementsat the beginning," says Russell, now an executiveprofessor at Northeastern Universitys College ofBusiness in Boston. "And the more precise you can
  32. 32. Baselines in the SDLC• Baselines are an important part of the SystemsDevelopment Life Cycle (SDLC). Thesebaselines are established after four of the fivephases of the SDLC and are critical to theiterative nature of the model.• Each baseline is considered as a milestone inthe SDLC.• Functional Baseline: established after theconceptual design phase.• Allocated Baseline: established after thepreliminary design phase.
  33. 33. Conclusion