Friday, May 30, 2008

Software Testing LifeCycle(STLC), V-MODEL



Software Test Life Cycle:

Software testing life cycle identifies what test activities to carry out to accomplish quality assurance process in a software development project.
There are different kinds of software development life cycle(SDLC) such as Waterfall, Spiral, Agile, and many others. Software testing has its own life cycle that intersects with every stage of the SDLC either it is Waterfall, Spiral or Agile. However, STLC varies from one to another based on size of project, test team, test in Scope/out of scope, and code release date (how frequently). So, knowledge about some of the major phase in STLC, quality assurance activities during phases and role of a tester, makes you as a tester always ready to accomplish your task with a mark. This picture describes one of widely used STLC phases.
Generally STLC for a single test cycle consists of phases: 1) Planning, 2) Analysis, 3) Design, 4) Initial Testing 5) Testing Cycles, 6) Final Testing and Implementation and 7) Post release
Planning :
  • High level test plan
  • Identify review process, Metrics
  • Bug reporting procedures
  • Acceptance criteria for QA
  • schedule
Analysis Phase:
  • Develop Test Case format , Validation Matrix
  • Develop, and plan Test Cycles matrices and time lines
  • Begin writing Test Cases based on Functional Validation matrix
  • Map baseline data to test cases to business requirements
  • Identify Automation, Manual and Types of testing ,
  • Test environment, automation system setup.
Design :
  • Test -plan(ning) review and verify.
  • Review matrix (coverage).
  • Continue working on Test Cases.(update, new )
  • Finalize test case selection for each cycle for manual run and automation.
Initial Testing
  • Complete all plans, Test Case, scripting
  • Unit test (Automated?)
Test Cycle:
  • Test Cycle 1, run first set of test
  • Report bugs - Triage(bug verification)- Bug fixes - Regression
  • Add test cases as required
  • Test Cycle 2, 3 ...
Final Testing and Implementation :
  • Code Freeze
  • Run Test cases for including performance level .
  • Communicate defect tracking metrics.
  • Regression
  • Documents.
Post Release
  • evaluation meeting - lesson learned
  • Prepare final Defect Report and metrics. Develop strategies to prevent similar problems in future project.
  • Milestones for improvements
  • Environment clean-up.clean (tag and archive tests and data for that release) restore test machines to baseline for next test cycle
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V-model



Although variants of the V-model exist, a common type of V-model uses four test levels, corresponding to the four development levels. The four levels used in this syllabus are:
component (unit) testing;
integration testing;
system testing;
acceptance testing.
In practice, a V-model may have more, fewer or different levels of development and testing, depending on the project and the software product. For example, there may be component integration testing after component testing, and system integration testing after system testing. Software work products (such as business scenarios or use cases, requirements specifications, design documents and code) produced during development are often the basis of testing in one or more test levels. References for generic work products include Capability Maturity Model Integration (CMMI) or ‘Software life cycle processes’. Verification and validation (and early test design) can be carried out during the development of the software work product