Slide 3 Flashcards
Why IS Projects Are Hard
- High Stakes
Capital and human resource intensive
Mission critical & highly visible - Complexity
Cross functional in nature
Large scale
Rapidly changing technology and requirements
What is systems development cycle (SDLC)
What: The activities that go into developing information system solutions to an organizational problem or opportunity
Formal process
Comprehensive (hopefully leaves no stones unturned)
Repeatable
How to create a systems development cycle (SDLC)
Analyze critical business processes
Break the opportunity/problem into pieces smaller and more manageable
a systems development cycle (SDLC):
the overall process for developing information systems from planning and analysis through implementation and maintenance (7 steps)
planning, analysis, design, development, testing, implementation, maintenance
SDLC, Planning phase
Planning phase – involves establishing a high-level plan of the intended project and determining project goals
SDLC - Systems Analysis- Planning :
Purpose:
Define the problem(s)
Identify the causes of the problem(s)
Specify potential solutions Determine if the potential solution(s) are achievable (Feasibility Study)
Types of Feasibility (systems analysis - planning)
Economic: Can we afford to do this, do the benefits outweigh the costs?
Technical: “Do H/W & S/W exist to do this?”
Operational: “Will this make us better?”, “Is the solution desirable within existing conditions”
Organizational: “Does it fit with our organization?”
Legal/Political: Stakeholder and regulatory analysis
Systems Analysis- Requirements Definition
- Purpose:
Define the information requirements and functions, resources and interfaces - Outputs:
Feasibility document (Planning document, Project gets a “Go/No Go!”)
Entity Relationship Diagrams w/o attributes
Management “signs off” on project
Systems Design purpose
Explains how the system will meet the informational requirements determined in the Systems Analysis Phase
“Blueprint” of how system is going to be built :
Conceptual Model:
Entity Relationship Diagrams w/ detail attributes describes information structures
Schematic Diagram (Data Flow Diagrams)
describes information flows
Logical Model:
Hierarchical, Network, Relational, Object-oriented model
Physical Model:
Actual hardware, software, telecommunications diagram (diagrams that show layout of how things will connect
Procurement of software solutions/ Potential Coding Modifications purpose
- Evaluation and selection of software
- System specifications prepared during the design phase are translated into software programming modifications if needed.
Testing purpose
To determine whether the system produces the desired results under know conditions
Alpha testing
User testing of a information system using simulated data – Normally done by the internal IS group
Beta testing
User testing of a completed information system using real data
Other different types of testing:
Unit testing – tests each module of software using true information the organization will use
Application (or system) testing – verifies that all units of code work together Integration testing – exposes faults in the integration of software components or units
Backup and recovery testing – tests the ability of an application to be restarted after failure
Documentation testing – verifies instruction guides are helpful and accurate
User acceptance testing (UAT) – tests if a system satisfies its acceptance criteria
Conversion/Implementation purpose
Implementation of new system and change over from old to new system
Conversion/Implementation approach
Installation of software/hardware solution
Make minor adjustments to system
Documentation
Train users
System testing/Beginning to use new system
Maintenance is:
Involves performing changes, corrections, additions, and upgrades to ensure the system continues to meet the business goals
Maintenance – fixing or enhancing an information system to meet the needs of organization and it’s customers
Maintenance purpose
System performance
] Respond to change
Continuous improvement Adding new modules of Enterprise Resource planning or Software as a Service contract.
Maintenance issues
Evaluation of proposed changes
Training on upgraded items.
Cost
Different types of maintenance include:
1) Adaptive maintenance : making changes to system to accommodate organization change and/or customer needs
2) Corrective maintenance: Correcting processes/features that don’t work correctly.
3) Perfective maintenance: Simply enhancing the system, not necessary but make system better
4) Preventative maintenance: like a system tune-up – Software upgrades, hardware upgrades, etc.