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Information System Development. Learning Outcomes. Students should be able to…. Discuss the importance of project management, feasibility assessment, documentation, data and information gathering techniques, and information systems security during system development.
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Learning Outcomes Students should be able to… Discuss the importance of project management, feasibility assessment, documentation, data and information gathering techniques, and information systems security during system development Discuss the purpose of each phase in the system development cycle
The System Development Life Cycle What is an information system (IS)? Hardware, software, data, people, and procedures that work together to produce quality information 1996 2007 System—Set of components that interact to achieve common goal Businesses use many types of systems
The System Development Life Cycle Phase 2. Analysis • Conduct preliminary investigation • Perform detailed analysis activities: • Study current system • Determine user requirements • Recommend solution Phase 1. Planning Phase 3. Design • Review project requests • Prioritize project requests • Allocate resources • Form project development team • Acquire hardware and software, if necessary • Develop details of system Phase 4. Implementation Phase 5. Operating, Support, and Security • Develop programs, if necessary • Install and test new system • Train users • Convert to new system • Perform maintenance activities • Monitor system performance • Assess system security What are the phases of the system development life cycle?
The System Development Life Cycle What are guidelines for system development? Arrange tasks into phases (groups of activities) Involve users (anyone for whom system is being built) Develop clearly defined standards (procedures company expects employees to follow)
The System Development Life Cycle Who participates in the system development life cycle? Stakeholders!
The System Development Life Cycle What is a systems analyst? A person!!! A person(s) playing the “role” of systems analyst is: Responsible for designing and developing information systems the “End Users” (stakeholders) primary contact person
The System Development Life Cycle What is theproject team? Formed to work on a project from beginning to end Consists of users, systems analyst, and other IT professionals Project leader — one member of the team who manages and controls the project budget and schedule
The System Development Life Cycle What is project management? • Process of planning, scheduling, and controlling activities during system development cycle • Project leader identifies elements for project Goal, objectives, and expectations, collectively called scope Required activities & roles played to fulfill the activities Time estimates for each activity Cost estimates for each activity Order of activities Activities that can take place at same time
The System Development Life Cycle What is a Gantt chart? • Popular tool used to plan and schedule time relationships among project activities
The System Development Life Cycle What is feasibility? Operational feasibility Measure of how suitable system development will be to the company Four feasibility tests: Schedule feasibility Economic feasibility (also called cost/benefit feasibility) Technical feasibility
The System Development Life Cycle What is documentation? Collection and summarization of data and information Includes reports, diagrams, programs, and other deliverables Online Help too!!!
The System Development Life Cycle What are six data and information gathering techniques? • Review documentation • Observe • Questionnaire • Interview • Joint-application design (JAD) session • Research JAD Session in Progress
The System Development Life Cycle What are some reasons to create or modify an information system? To correct problem in existing system To improve existing system Outside group may mandate change Competition can lead to change
The System Development Life Cycle What is the planning phase? Begins when steering committee receives project request Steering committee — decision-making body for the company Function of committee: Review and approve project requests Prioritize project requests Allocate resources Form project development team for each approved project
The System Development Life Cycle Conduct preliminary investigation, also called feasibility study Perform detailed analysis What is the analysis phase? Operational feasibility Four feasibility tests: Schedule feasibility Technical feasibility Economic feasibility
The System Development Life Cycle What are possible solutions? Horizontal market software—meets needs of many companies Buypackaged software —prewritten software available for purchase Vertical market software—designed for particular industry Write own custom software —software developed at user’s request Outsource — have outside source develop software
The System Development Life Cycle What is the design phase? Acquire hardware and software Develop all details of new or modified information system Includes several activities Database design Input and output design Program design
The System Development Life Cycle What is a prototype? A working model of the proposed system Mockupis a sample of input and/or output:
The System Development Life Cycle What is computer-aided software engineering (CASE)? • Software tools designed to support activities of the system development life cycle • Two popular Examples: • Microsoft’s Visual Studio • Eclipse
The System Development Life Cycle What is the implementation phase? • Purpose is to construct, or build, new or modified system and then deliver it to users Convert to new system Progression Train users Install and test new system Develop programs
The System Development Life Cycle What are the four types of tests performed by system developers? Unit Test Systems test Verifies each individual program works by itself Verifies all programs in the application work together Integration Test Acceptance Test Verifies application works with other applications Verifies the new system works with actual data
The System Development Life Cycle What are conversion strategies? • Used to switch from old system to new system
The System Development Life Cycle Perform maintenance activities What is the operation, support, and security phase? Monitor system performance • Provides ongoing assistance after system is implemented Assess system security
The System Development Life Cycle CLICK TO START Video: A Tour of Lucasfilm’s Data Center
Programming Languages What is a computer program (software)? • Set of instructions that directs the computer to perform tasks • Programming language—used to communicate instructions
Programming Languages…”in the beginning” What is machine language? • Only language computer directly recognizes • Uses a series of binary digits (1s and 0s) with a combination of numbers and letters that represent binary digits
Programming Languages…a wee-bit newer What is assembly language? • Instructions made up of symbolic instruction codes, meaningful abbreviations and codes • Source program contains code to be converted to machine language
Programming Languages…1960’s until now What is COBOL? • COmmon Business-Oriented Language • Designed for business applications • English-like statements make code easy to read, write, and maintain
Programming Languages…many more today What are C, C++, C#, Visual Basic, Java, JavaScript, Perl, PerlScript, PHP, Ruby on Rails, Cold Fusion… • Powerful languages • Requires professional programming skills (or at least training of yourself)
Programming Languages What is a compiler? • A program (software) that converts the entire source program into machine language before executing it
Programming Languages What is an interpreter? • A program that translates and executes one program code statement at a time • Does not produce an object program Browsers do this! (For example, Firefox or Internet Explorer)
Programming Languages…many, many more What are other available programming languages? ADA ALGOL APL BASIC FORTH FORTRAN HYPERTALK LISP LOGO MODULA-2 PASCAL PILOT PL/1 PROLOG SMALLTALK
Programming Languages What is an application generator? • Program that creates source code or machine code from a specification • Consists of a report writer, a form, and menu generator Microsoft Access
Programming Languages What is HTML(Hypertext Markup Language)? • Used to create Web pages Source Code: WYSIWYG (“wiz-e-wig”) What You See is What You Get: View -> Source
Programming Languages What is a scripting language? • Programming language used to allow Web pages to be more “powerful” (do more things) Examples: • JavaScript • VBScript • Perl
Programming Languages What is dynamic HTML (DHTML)? • Enhanced version of HTML which allows developers to include more graphical interest and interactivity on Web pages
Programming Languages What are XML and WML? XML (Extensible Markup Language)allows developers to create customized tags Server sends entire record to client, enabling client to do much of processing without going back to the server <LastName>Norman</LastName> <FirstName>Ronald</FirstName> <College>Grossmont</College> <OfficePhone>619-644-7515</OfficePhone> Office 2007 default document Format is XML: .docx, .xlsx, .pptx Many PDAs and smart phones use WML as their markup language WML (Wireless Markup Language)allows developers to design pages specifically for microbrowsers
Programming Languages What is Web page authoring software? • Creates sophisticated Web pages without using HTML • This software generates (creates) the HTML code for you Examples of Web page authoring software
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