Planning and Installing a System

Legacy systems and compatibility issues

• Legacy system: Any system technology method or application program that is older than the current version
• May or may not be supported/available for purchase

Mergers

• If companies/organizations merge across international borders there may be issues like:
• Software compatibility
• Language differences
• Time zone differences
• Workforce cultural differences

Implementation of systems

Local software vs Remote software

• Two models for distributing software: Local (On premise) and Remote (Cloud-based, SaaS)
• Local: Installed on a computer (e.g. DVD installation)
• Remote: Accessed via the internet (e.g. PlayStation Store)

SaaS (Software-as-a-Service)

• Software distribution model where a third-party provider hosts applications over the internet

Benefits of being "Cloud-based"

• SaaS minimizes IT costs
• Reduction in staff workload
• Fast recovery from service outages

Drawbacks of SaaS

• Software integration headaches
• Security concerns (identity and access management)
• Government compliance regulations for storing customer data

Installation processes

4 installation methods

• Direct changeover
• Parallel running
• Pilot running
• Phased conversion

Direct Changeover

• Stop using the old system and start with the new one
• Advantages: Minimal time and effort
• Disadvantages: No fallback if new system fails

Parallel running

• Run both systems side by side until the new system works well
• Advantages: Backup with the old system
• Disadvantages: Expensive and time-consuming

Pilot running

• Test the system with a small subset of the organization
• Advantages: Trial system, fewer risks for small group
• Disadvantages: No backup for pilot group

Phased conversion

• Introduce the new system in phases, replacing parts of the old one
• Advantages: Allows gradual training
• Disadvantages: No fallback for converted sections

Data migration

Moving data between systems

Incompatible file formats

• Software versions might not be compatible

Data structure differences

• Moving data from one format to another can cause issues

Validation rules

• If validation rules differ between systems, data can be lost

Testing

• Functionality testing
• User experience testing
• Performance and load testing
• Compatibility testing
• Security testing (PenTesting)

Static vs Dynamic testing

• Static: Reviews or inspections without running the code
• Dynamic: Running code with test cases

Alpha vs Beta testing

• Alpha: Performed by internal employees
• Beta: Performed by clients or end-users

Black-box vs White-box testing

• Black-box: Functional testing without internal knowledge
• White-box: Testing with knowledge of internal code

User acceptance testing

• Ensures the system meets the end user's needs

Automated testing

• Automated software tools are used to perform testing