Overview of Systems Development

  

Overview of Systems Development



  Participants 

  Initiating systems development 

  Information systems planning 

  Establishing objectives for systems development 

  Systems development and the Internet 

  Trends in systems development and enterprise resource planning Participants 

  Stakeholders 

  Individu / organisasi yang merupakan penerima manfaat dari upaya pengembangan sistem 

  Systems analyst 

  Profesional yang mengkhususkan diri dalam menganalisis dan merancang sistem bisnis 

  Users 

  Individu yang berinteraksi dengan sistem secara teratur 

  Programmer 

  Individu yang bertanggung jawab untuk memodifikasi

  Systems analyst Managers

  System stakeholders Users

  Technical specialists Programmers

Systems Analyst

• • Seorang programmer atau konsultan yang merancang

  dan mengelola pengembangan aplikasi bisnis.

• • Biasanya, sistem analis lebih terlibat dalam masalah

  desain daripada di hari-hari coding.

Alasan khas untuk Memulai Pengembangan Sistem Proyek

  Keinginan untuk membuat lebih efektif menggunakan informasi Masalah dengan sistem yang ada

  Keinginan untuk memanfaatkan peluang-peluang baru Meningkatnya persaingan

  Pertumbuhan organisasi Merger atau akuisisi

  Perubahan pasar atau lingkungan eksternal Persepsi manfaat

  Potensial oleh Individu mampu melakukan perubahan

  Proses Sistem pembangunan dimulai Planning 

  Perencanaan sistem informasi 

  penerjemahan tujuan strategis dan Strategic plan organisasi ke dalam inisiatif pengembangan sistem

   Analisis Kreatif

  

  Investigasi pendekatan baru untuk masalah yang ada

  IS planning

   Analisis Kritis 

  Mempertanyakan berisi dan hati- hati apakah unsur-unsur sistem yang terkait dalam cara yang paling efektif atau efisien

  Systems development initiatives

Langkah-langkah dalam Perencanaan IS

  Strategic plan Mengembangkan tujuan keseluruhan

  Identify IS projects Set prioritas & pilih proyek

  Analisis kebutuhan sumber daya Jadwal yang ditetapkan dan batas waktu

  Proyek sistem sebelumnya tidak direncanakan Menetapkan Tujuan Pembangunan Sistem 

  Performance objectives 

  Kualitas atau kegunaan dari output 

  Kualitas atau kegunaan dari format output 

  Kecepatan di mana output yang dihasilkan 

  Cost objectives 

  Biaya pengembangan 

  Biaya yang berkaitan dengan keunikan sistem aplikasi 

  

Investasi tetap di hardware dan peralatan terkait



  On-akan biaya operasi dari sistem Systems Development and the Internet 

  Aplikasi dipindahkan ke Internet 

  Penjualan  penempatan order

   Akses informasi produk

   Membangun situs Web statis

   Intranet tools

   NetDynamics

   SilverStream

   Web-Logic

   Novera Systems Development Life Cycle 

  Systems investigation

  It’s a

   Masalah dan peluang diidentifikasi

  “cycle”

   Systems analysis  sistem yang ada dan proses kerja dipelajari

   Systems design

   Mendefinisikan bagaimana sistem informasi akan melakukan apa yang harus dilakukan untuk memecahkan masalah

   Systems implementation

   Komponen sistem dirakit dan sistem baru atau diubah ditempatkan ke dalam operasi

   Systems maintenance and review

   Memastikan sistem beroperasi dan dimodifikasi untuk

  

Systems maintenance

and review

(Mengevaluasi hasil solusi)

Systems implementation

(Solusi tempat berlakunya)

Systems design

  

(Memilih dan merencanakan solusi terbaik)

Systems Analysis

(Memahami solusi)

Systems investigation

  

(Memahami masalah)

  Biaya untuk membuat perubaha n tertentu

  Investigation Analysis Design Implementation Maintenance and review Prototyping 

  Operational prototype 

  Mengakses file data real, mengedit input data, membuat perhitungan yang diperlukan dan perbandingan, dan menghasilkan output riil

   Non-operational prototype

  

  Sebuah model yang mencakup output dan input spesifikasi dan format

   Rapid application development (RAD)

  

  Mempekerjakan alat, teknik, dan metodologi yang dirancang untuk mempercepat pengembangan aplikasi, secara otomatis sumber generasi kode, dan memfasilitasi keterlibatan pengguna dalam kegiatan desain dan pengembangan

   Joint application development (JAD) 

  Melibatkan pertemuan kelompok di mana pengguna, stakeholder, dan IS profesional bekerja sama untuk menganalisis sistem yang ada, solusi yang

Rapid Application Development

  A programming system that enables programmers to quickly build working programs. In general, RAD systems provide a number of tools to help build graphical user interfaces that would normally take a large development effort. Two of the most popular RAD systems for Windows are Visual Basic and Delphi.

  Historically, RAD systems have tended to emphasize reducing development time, sometimes at the expense of generating efficient executable code. Nowadays, though, many RAD systems produce extremely fast code. Conversely, many traditional programming environments now come with a number of visual tools to aid development. Therefore, the line between RAD systems and other development environments has become blurred.

Prototyping: The Iterative Life Cycle

  Determine requirements Analyse alternatives

  Specify design Implement design

  User review Iteration 1

  Determine requirements Analyse alternatives

  Specify design Implement design

  User review Iteration 2

  Determine requirements Analyse alternatives

  Specify design Implement design

  Changeover Iteration 3 (final) General Model of Prototyping

  Systems development initiated Investigate and analyse problem sufficiently to develop workable solution

  Develop prototype Put prototype into operation

  Refine and modify prototype Complete component or system End-User Systems Development Life Cycle  End-user systems development life cycle

   Setiap proyek pengembangan sistem di mana upaya primer dilakukan dengan kombinasi manajer bisnis dan pengguna Factors Affecting Systems Development Success 

  Managing change 

  Requires the ability to recognize existing or potential problems and deal with them before they become a serious threat to the success of a new or modified system

   Use of project management tools

   Schedule

   Milestone

   Deadline

   Critical path

   Program Evaluation Review Technique (PERT)

   Gantt chart

  

Selected Project Management

Software Packages Software

Vendor BeachBox ’98

  NetSQL Partners

Job Order Management Software Inc.

  OpenPlan Welcom Project Microsoft Project Scheduler Scitor Corp. Super Project Computer Associates

  

Use of Computer-Aided Software

Engineering (CASE) Tools 

  CASE tools automate tasks required in a system

development effort and enforces adherence to the SDLC



  Upper CASE tools 

  Tools that focus on activities associated with the early stages of systems development  Lower CASE tools

  

Tools that focus on the later implementation stage of systems

development

   Integrated-CASE (I-CASE) tools

   Tools that provide links between upper- and lower-CASE packages,

allowing lower-CASE packages to generate program code from CASE

  Short for Computer Aided Software Engineering, a category of software that provides a development environment for programming teams. CASE systems offer tools to automate, manage and simplify the development process. These can include tools for:

• Summarizing initial requirements
• Developing flow diagrams
• Scheduling development tasks
• Preparing documentation
• Controlling software versions
• Developing program code

  Various companies offer CASE software capable of supporting some or all of these activities. While many CASE systems provide special support for object-oriented programming, the term CASE can apply to any type of software evelopment environment.

  ISO 9000

 An international standard used by IS departments to

ensure quality standards exist and are maintained in their products and services

  Systems Investigation 

  Identify potential problems and opportunities and consider them in light of the goals of the company  The investigation team

   Managers and stakeholders

  

  IS personnel 

  Task 

  Undertake feasibility analysis 

  Establish system development goals 

  Select system development methodology 

  Prepare system development report Feasibility Analysis 

  Technical feasibility 

  Can the hardware, software, and other system components be acquired or developed to solve the problem? 

  Operational feasibility 

  Can the project be put into action or operation? 

  Schedule feasibility 

  Can the project be completed in a reasonable amount of time? 

  Economic feasibility 

  Does the project make financial sense? 

  Net present value 

  The preferred approach for ranking competing projects and The Systems Investigation Report  A report that summarizes the results of the systems investigation and the process of feasibility analysis and recommends a course of action

   Steering committee

   An advisory group consisting of senior management and users from the IS department and other functional areas Systems Analysis

 Typical table of contents from a systems investigations

report:

  

Table of Contents

  1. Executive summary

  2. Review of goals and objectives

  3. System problems and opportunities

  4. Project feasibility

  5. Project costs

  6. Projects benefits

  7. Recommendations Sources of Data Internal Sources

  External Sources

• Users, stakeholders, managers
• Organization charts
• Forms and documents
• Procedure manuals and policies
• Financial reports
• IS manuals
• Other measures of business
>Customers • Suppliers • Stockholders • Government agencies
• Competitors • Outside groups • Journals, etc.
• Consultants

Data Collection 

  Structured Interview 

  Unstructured Interview 

  Direct Observation 

  Questionnaires 

  Identify data sources Data collection

Statistical Sampling

  Follow-up & clarification Data Analysis 

  Data analysis 

  Manipulating collected data so that it is usable for the development team members participating in systems analysis 

  Data modeling 

  A commonly accepted approach to modeling organizational objects and associations that employ both text and graphics 

  E.g, ER (entity relationship) diagrams 

  Activity modeling 

  A method to describe related objects, associations, and activities 

  Data flow diagram 

  

A diagram that models objects, associations, and activities by ER Example

  Play Member Game of Golf

  MID Name Address

  Date paid Date Time Score

  1 

  MID Data Flow Diagram  Schematic description of business processes

   Premise: for every activity there is some communication,

transference, for flow that can be described as a data

element

   DFDs show “logical” sequences (not physical processes)

  Process Entity symbol Data-flow line Data-flow line Data store symbol

  Tee time Available times Assign

  Member Schedule

  Tee time Reservation request Group information

  Member Course access

  Check tee time member

  Member Member card in

  Member ID Date

  Sort Score card Score card

  Member scores

  Scores Handicap

  Calculate Tee time handicap Application Flowchart 

Charts that show relationships among applications or systems

  Order processing application Inventory control application

  Invoicing application Marketing analysis application Grid Charts 

  A table that shows relationships among the

various aspects of a systems development effort

  Database Customer Inventory Supplier Accounts receivable applications database database database database Order processing applications

X X

  Inventory control application

X X

  Marketing analysis application

  X Invoicing Requirements Analysis 

An assessment used to determine user, stakeholder, and organizational needs

  Strategy translation Goals and mission

  Systems of the organization requirements Screen Layout Charts 

  May be tailored for… 

  Frequent users who require little descriptive information, or  Infrequent users who require more descriptive information ITEM NO. QTY UNIT PRICE DOLLARS DISCOUNTS

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  For frequent users…

  For infrequent users…

Which online option would you like to perform? (Please enter an ‘X’ to make a selection)

  

_DATA ENTRY Enter transaction and report requests for later processing _RETRIEVALS Review online information from the database: bill of materials, where-used, routing, item data The Systems Analysis Report  Strength and weaknesses of existing system from a stakeholder’s perspective

  

User/stakeholder requirements for the new system

   Organizational requirements

   Description of what new information systems should do to solve the problem

Typical Table of Contents for a Report on an Existing System

  

Johnson & Flores, Inc.

Systems Analysis Report

TABLE OF CONTENTS

  Background Information Problem or Need Statement Data Collection Data and Requirements Analysis Recommendations Appendixes of Documents, Tables, and Charts Glossary of Terms End of Chapter 12