Professor Michael J. Losacco CIS 1110 – Using Computers System Development & Programming Chapter 11

Chapter11 2/44 Overview Define System Development List the System Development Phases Explain Activities for Each Phase Explain High- & Low-level Languages Detail Steps of Program Development

Chapter11 3/44 Information System Hardware Software Data People Procedures Together Produce Information Interact to Achieve Common Goal

Chapter11 4/44 System Development Phases

Chapter11 5/44 Guidelines Arrange Tasks Into Phases Groups of Activities Involve Users Anyone for Whom System is Being Built Develop Clearly Defined Standards Sets of Rules & Procedures Company Expects Employees to Follow

Chapter11 6/44 Initiation Correct Problem in Existing System Improve Existing System Outside Group May Mandate Change Competition Can Lead to Change Request for System Services AKA Project Request Request for New / Modified System

Chapter11 7/44 Participants Representatives from Departments Involved in Building or Using System

Chapter11 8/44 Project Management Project Manager Plans, Schedules, & Controls Activities Establishes Scope Goals, Objectives, & Expectations of Project List Required Activities Time Required Cost Estimate Order & Dependency

Chapter11 9/44 Project Success Successful On-time, On-budget, All Features Challenged Late, Over Budget, Less Features Failed Cancelled or Delivered but Never Used Standish Group 2009

Chapter11 10/44 Project Success Smaller Projects Have Better Success Standish Group

Chapter11 11/44 Project Success Shorter Projects Have Better Success Standish Group

Chapter11 12/44 Project Success Average Percentage Above Estimate Standish Group

Chapter11 13/44 Project Success Notable Project Failures FAA Air Traffic Control $1.5B – 1994 IRS Modernization $3.4B – 1997 DoD Business Modernization $19B – Inventory / 450 Personnel Systems Children’s Hospital of Pittsburgh Dramatically Higher Death Rates – 2002

Chapter11 14/44 Planning Phase Steering Committee Decision-making Body for Company Receives Project Requests Function of Committee: Review & Approve Project Prioritize Requests Allocate Resources Form Project Development Team

Chapter11 15/44 Analysis Phase Preliminary Investigation Determine Nature of Problem Determine Whether it is Worth Pursuing Feasibility Study Economic AKA Cost / Benefit Operational Schedule Technical

Chapter11 16/44 Analysis Phase Detailed Analysis Study How Current System Works Determine User’s: Wants Needs Recommend Solution

Chapter11 17/44 Analysis Phase Documentation Collect & Summarize Data & Information Reports Diagrams Programs Other Deliverables

Chapter11 18/44 Analysis Phase Data & Information Gathering Review Documentation Research Questionnaire One-on-one interview Observation Joint-application Design (JAD) Session

Chapter11 19/44 Analysis Phase Process Modeling AKA Structured Analysis & Design Transform Inputs into Outputs Entity-relationship Diagrams Data Flow Diagrams Project Dictionary

Chapter11 20/44 Analysis Phase Entity-relationship Diagram Shows Connections Between Entities Entities Objects in System that Have Data

Chapter11 21/44 Analysis Phase Data Flow Diagram Shows Flow of Data in System

Chapter11 22/44 Analysis Phase Project Dictionary Structured English Used to Explain Details of Process

Chapter11 23/44 Analysis Phase Project Dictionary Decision Table / Tree Logical Conditions & Actions

Chapter11 24/44 Analysis Phase Project Dictionary Data Dictionary Stores Details About Each Data Item

Chapter11 25/44 Analysis Phase System Proposal Assess Each Alternative Solution Recommend Most Feasible Solution Steering Committee Has to Approve ROI Hard v. Soft

Chapter11 26/44 Analysis Phase Possible Solutions Packaged Prewritten Software Available for Purchase Horizontal Meets Needs of Many Companies Vertical Designed for Specific Industry Custom Write Own Software Outsourcing Hire Outside Company to Perform Work

Chapter11 27/44 Analysis Phase Outsourcing Senior Resource Salaries PayScale 2009

Chapter11 28/44 Design Phase Develop All Details of System Write Technical Specifications Details Functionality & Scope of Project Request for Information (RFI) Request for Quotation (RFQ) Vendor Quotes Price For Listed Hardware Request for Proposal (RFP) Vendor Quotes Price For Software Based on Specification

Chapter11 29/44 Design Phase Acquire Hardware & Software Solicit / Test / Evaluate Vendor Proposals References from Vendor Talk to Current Users Demonstrations Trial Version Benchmark Test Measures Performance Prototype (Proof of Concept) Working Model of Proposed System

Chapter11 30/44 Design Phase Acquire Hardware & Software Turnkey Solution Complete System Provided by VAR Value-added Reseller Purchases Products from Manufacturer Resells Them, Offering Additional Services Must Meet Certain Requirements

Chapter11 31/44 Design Phase Inspection Step-by-step Review of Deliverables By Project Team & Users Uses Final Review of Specification Before Submitted to Programming Team Identify & Correct Any Errors

Chapter11 32/44 Implementation Phase Build System & Deliver it to Users Develop Programs Test & Install Train Users Convert to New System

Chapter11 33/44 Implementation Phase Develop Programs Programmers Write Code to Specification Follow Program Development Life Cycle Analyze the Requirements Design the Solution Validate the Design Implement the Design Test the Solution Document the Solution

Chapter11 34/44 Implementation Phase Testing Unit Each Individual Program Works System All Programs in Application Work Together Integration Application Works With Other Applications Acceptance Verifies New System Works with Actual Data

Chapter11 35/44 Implementation Phase Testing Phases Alpha Performed by Employees Beta Performed by Customers Training Show Users How to Use New System Scheduling Conflicts

Chapter11 36/44 Implementation Phase Convert to New System Transition from Old to New System Pilot Most Widely Used

Chapter11 37/44 Support Phase Ongoing Support After Implementation Conduct Post-implementation Review Perform Maintenance Activities Identify & Correct Errors Identify Enhancements Monitor System Performance Assess System Security

Chapter11 38/44 Computer Program Set of Instructions Directs Computer to Perform Tasks Language Set of Words, Symbols, & Codes Communicates Instructions to Computer

Chapter11 39/44 Languages Categories Low-level Languages Machine Dependant Typically Determined by Processor Machine & Assembly Faster Execution, More Code Required High-level Languages Machine Independent Third, & Fourth Generation Slower Execution, Less Code Required

Chapter11 40/44 Program Development Development Options Make (Create In-house) More Control Buy (Acquire from Software Vendor) Lower Overall Cost Higher Quality Faster Implementation Less Staff Required

Chapter11 41/44 Analyze Requirements Review Requirements Meet with Systems Analyst & Users Identify Input Processing Output Data

Chapter11 42/44 Design Solution Devise Solution Algorithm Step-by-step Procedure to Solve Problem Flowchart Conveys Logic Graphically Pseudocode Uses Condensed English to Convey Logic

Chapter11 43/44 Implement Design Write Code Translate Design into Program Syntax Rules that Specify How to Write Instructions Comments Program Documentation Create User Interface

Chapter11 44/44 Test Solution Ensure Program Runs Correctly Error Types Syntax Logic Run time Debugging Locate & Correct Syntax & Logic Errors