What are the Goals of System Test?

The goals of system test include:

• Breaking the system
• Demonstrating readiness for use
• Understanding performance limits
• Test user procedures

Criteria of a System Test

Criteria of a System Test includes:

• Compliance with Functional Requirements
• Performance at all Interfaces
• Performance at Boundaries and under stress
• Adequacy of user documentations

What is System Testing?

System Testing:

• Measures compliance with system objectives
• Tests functional requirements and system requirements
• Uses system test environment setup by testing team

The Trend in Integration Test

The trend in Integration Test:

• traditional top-down or bottom-up approaches favour the developers
• the functional approach favours the testers
• the object-oriented approach naturally leads the developers into functional integration

Advantages and Disadvantages of Functional Integration

Advantage:

• Accomplishes system function

Disadvantages:

• May be hard to define data to test lower level module conditions
• May be hard to locate faults

What is Functional Integration?

Functional Integration:

• Start with a specific function
• Use incomplete components, stubs and drivers as needed to conduct testing
• Progress to multiple functions
• Functional cases may be usable for system testing

Disadvantages of Bottom-Up Integration

Disadvantages of Bottom-Up Integration includes:

• Cases may not be usable at the system level
• May be hard to detect interface faults
• major design faults will be detected late

Advantages of Bottom-Up Integration

Advantages of Bottom-Up Integration includes:

• Easy to locate faults
• Does not need stubs

What is Bottom-Up Integration?

Bottom-Up Integration is:

• Driver is built to quality software modules
• Modules are linked when a driver can be replaced by a new module and all modules called by the new module have been qualified

Disadvantages of Top-Down Integration

Disadvantages of Top-Down Integration includes:

• May be hard to define and input data to test lower level module conditions
• Lower level modules are not tested as frequently as upper level modules
• Functionality may be severely limited or smart stubs required

Advantages of Top-Down Integration

Advantages of Top-Down Integration includes:

• Accomplishes "working" system
• Easy to locate faults
• Does not need drivers

What is Top-Down Integration?

Top-Down Integration is:

• Start with control modules
• Add a few modules for each build
• Data injected from "qualified" modules
• Missing modules simulated with stubs

Supporting Software in Integration Test

Some supporting software in Integration Test include:

• Drivers
  Programs that invoke the software being tested and simulate the activity of higher level application components. They usually provide test input and report test result.
  
  
• Stubs
  Dummy program modules used to enable the testing of higher-level invoking components. Their functional capabilities range from none to extensive simulations of actual application modules.