INFORMATION GOVERNANCE
Kpatel
PPTs-TheSystemDevelopmentLifeCyclewithnotes.pptxIntroduction
Developing of an information system may fail.
There are many factors that must be considered and come together in order to develop a successful information system.
The SDLC = Systems Development Life Cycle is one approach to reduce the risk of failure.
What do businesses build information systems?
How does the business though when it is time to replace the old information system with a new one?
Typically: workers will request new systems to help them perform their work.
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The System Development Life Cycle
What is an information system (IS)?
Hardware, software, data, people, and procedures that work together to produce quality information
System—Set of components that interact to achieve common goal
Businesses use many types of systems
The System Development Life Cycle
What are the phases of the system development cycle?
Phase 1. Planning
Phase 2. Analysis
Phase 3. Design
Phase 4. Implementation
Phase 5. Support
Review project requests
Prioritize project requests
Allocate resources
Identify project development team
Conduct preliminary investigation
Perform detailed analysis activities:
Study current system
Determine user requirements
Recommend solution
Acquire hardware and software, if necessary
Develop details of system
Develop programs, if necessary
Install and test new system
Train users
Convert to new system
Conduct post-implementation system review
Identify errors and enhancements
Monitor system performance
There are literally hundreds of activities associated with each phase of the SDLC
Such activities include:
Determining budgets
Gathering systems requirements
Documentation
Modeling
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Arrange tasks into phases (groups of activities)
The System Development Life Cycle
What are guidelines for system development?
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?
The System Development Life Cycle
What is a systems analyst?
Responsible for designing and developing information system
Liaison between users and IT professionals
The System Development Life Cycle
What is the project team?
Consists of users, systems analyst, and other IT professionals
Formed to work on project from beginning to end
Project leader—one member of the team who manages and controls project budget and schedule
The System Development Life Cycle
What is feasibility?
Measure of how suitable system development will be to the company
Operational feasibility
Schedule feasibility
Four feasibility tests:
Technical feasibility
Economic feasibility (also called cost/benefit feasibility)
The System Development Life Cycle
What is documentation?
Includes reports, diagrams, programs, and other deliverables
Collection and summarization of data and information
The System Development Life Cycle
What are six data and information gathering techniques?
Review documentation
Observe
Questionnaire
Interview
Joint-application design (JAD) session
Research
The System Development Life Cycle
What are some reasons to create or modify an information system?
Competition can lead to change
To improve existing system
Outside group may mandate change
To correct problem in existing system
The System Development Life Cycle
What is a request for system services?
Formal request for new or modified information system
Also called project request
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
Allocate resources
Form project development team for each approved project
Prioritize project requests
Planning phase - involves determining a solid plan for developing your information system.
The three of the most important activities involved during the planning phase:
Identify and select the system for development
Set project scope
Develop project plan
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The System Development Life Cycle
What is the analysis phase?
Conduct preliminary investigation, also called feasibility study
Perform detailed analysis
The System Development Life Cycle
What is the preliminary investigation?
Determine exact nature of problem or improvement and whether it is worth pursuing
Findings are presented in feasibility report, also known as a feasibility study
The System Development Life Cycle
What is detailed analysis?
Sometimes called logical design
2. Determine user’s wants, needs, and requirements
3. Recommend solution
1. Study how current system works
The analysis phase involves
The end users
The IT specialists
Working together to understand and document the business requirements for the system.
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Presented to steering committee, which decides how system will be developed
The System Development Life Cycle
What is the system proposal?
Assesses feasibility of each alternative solution
Recommends the most feasible solution for the project
The System Development Life Cycle
What are possible solutions?
Buy packaged software—prewritten software available for purchase
Outsource—have outside source develop software
Write own custom software—software developed at user’s request
Vertical market software—designed for particular industry
Horizontal market software—meets needs of many companies
The System Development Life Cycle
What is the design phase?
Acquire hardware and software
Develop all details of new or modified information system
The primary goal of the design phase
Build the technical architecture required to support the system.
This includes
Design of the technical architecture
Design system models.
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Visit vendors’ stores
The System Development Life Cycle
What is needed to acquire new hardware and software?
Identify all hardware and software requirements of new or modified system
Surf Web
Read print and online trade journals, newspapers, and magazines
Talk with other systems analysts
Technical architecture –
Defines the hardware, software, and telecommunications equipment required to run the system.
The final architecture must meet you needs in terms of
Time
Cost
Technical feasibility
Flexibility
It is important to ensure that the final architecture meet
Current system needs
Future system needs
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The System Development Life Cycle
What are three basic documents used to summarize technical specifications?
Less formal method that uses standard form to request information about product or service
Vendor quotes price(s) for listed product(s)
Vendor selects product(s) that meet(s) your requirements and then quotes price(s)
Identifies product(s) you want
Request for information (RFI)
Request for proposal (RFP)
Request for quotation (RFQ)
The System Development Life Cycle
How do systems analysts test software products?
References from vendor
Talk to current users of product
Product demonstrations
Trial version of software
Benchmark test measures performance
The System Development Life Cycle
What is a detailed design?
Includes several activities
Database design
Input and output design
Program design
Detailed design specifications for components in proposed solution
The System Development Life Cycle
What is a mockup?
Sample of input or output that contains actual data
The System Development Life Cycle
What is a prototype?
Working model of proposed system
Beginning a prototype too early may lead to problems
The System Development Life Cycle
What is computer-aided software engineering (CASE)?
Software tools designed to support activities of system development cycle
Convert to new system
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
Train users
Install and test new system
Develop programs
Implementation phase
Bringing the system into life by placing it in the organization
During this phase
You distribute the system to all of the knowledge workers and they begin using the system to perform their everyday jobs.
You create User documentation
Highlights how to use the system.
You perform training to the employees to use the system
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The System Development Life Cycle
What are the three types of tests performed by system developers?
Verifies application works with other applications
Systems test
Integration Test
Unit Test
Verifies each individual program works by itself
Verifies all programs in application work together
Testing is critical
Must have test plans
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The System Development Life Cycle
What is training?
Showing users exactly how they will use new hardware and software in system
Online training - runs over the Internet
Workshop training - is held in a classroom environment and lead by an instructor.
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The System Development Life Cycle
What is the support phase?
Conduct post-implementation system review—meeting to find out if information system is performing according to expectations
Identify errors
Identify enhancements
Monitor system performance
Provides ongoing assistance after system is implemented
Once the system is in place you need to provide support
Build a help desk to support the system users.
Provide an environment to support system changes.
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