九：Testing the System

一、Principles of system testing

1.Sources of software faults

【选择题】

• Typical exceptions do not include ( system crash ).
  include：
  • failure to provide a service
  • providing the wrong service or data
  • corrupting data

2.System testing process

3.Configuration management

Versions and releases
Regression testing
Deltas, separate files, and conditional compilation
Change control

4.Test team

二、Function testing

Purpose and roles
Cause-and-effect graphs

三、Performance testing

Purpose and roles
Types of performance testing

四、Reliability可靠性, availability可用性, and maintainability可维护性

1.Definition

【简答题】

• Define software reliability, maintainability and availability.
  可靠性：指一个系统对于给定的时间间隔内、在给定条件下无失效运作的概率。
  可用性：指在给定的使用时间点上，一个系统能够按照规格说明正确运作的概率。
  可维护性：指在给定的使用条件下，在规定的时间间隔内，使用规定的过程和资源完成维护活动的概率。

2.Measurement

• Reliability可靠性：MTTF/(1+MTTF)，the inter-failure times
• availability有效性：
• maintainability可维护性：1/(1+MTTR)，it takes to fix a faulty software
  【选择题】
• A measure of a system’s ( Software reliability ) is defined as MTTF/(1+MTTF), where MTTF is the average of the inter-failure times, i.e. Mean Time to Failure.
• A measure of a system’s ( Software maintainability ) is defined as 1/(1+MTTR), where MTTR is the average time it takes to fix a faulty software.

五、Acceptance testing

Purpose and roles
Types of acceptance tests

六、Installation testing

七、Test documentation

Test plan – test specification and evaluation – test description — test analysis report