Information Systems Development
Systems Development Life-Cycle
Methodologies & Commercial Alternatives
Traditional SDLC
•
Initial
Investigation (Feasibility)
•
Systems
Analysis
•
Systems
Design
•
Systems
Development (Programming)
•
Testing
•
Implementation
•
Use
•
Maintenance
Measuring Feasibility
•
Economic
–
Years
to Breakeven
–
Return
on Investment
•
Technical
–
Physical
requirements
–
HR
requirements
•
Operational
–
Business
needs
–
Interface
with other systems
Economic Analysis Example
•
A marketing rep
suggests your company create a data warehouse that would list perspective
customers. He asserts such a list would
increase sales 20% and profits 20% (about $60K/yr). Your quick analysis shows the hardware and software purchase
costs will be $100,000 with license fees of $12,000 after the first year. Is it feasible?
Systems Analysis
•
Review current system
•
Review current business
processes
•
Examine proposed
changes
•
Methods: error reports, company records, observation,
interviews, benchmarks and best practice models
Systems Design
•
System inputs, outputs,
and user interfaces
•
Description of
hardware, software, databases, networks, personnel, and procedures
•
System integration
detail
Development
•
Build
–
Programming tools
–
Modular design
–
Reuse
•
Purchase
–
RFP
–
Checklist/benchmarks/points
Testing
•
Modular testing
•
Integrative testing
•
Test sets
•
Beta releases
Implementation
•
Installation, training,
use
•
Phased
•
Parallel
•
Direct
Maintenance
•
Corrective
•
Perfective
•
Adoptive
Alternative Strategies
•
End-user
computing
–
Speed
and knowledge vs connectivity and standards
•
External
Acquisition
–
Increasing
supply of off-the-shelf systems
–
Adjusting
local processes to business standards
- Beware the integration
challenge – vanilla versus customization
•
Outsourcing
–
Core
competencies
–
Local
control
– Access to
expertise
- ERPS