A Detailed Guide on the Software Testing Life Cycle

What is the Software Testing Life Cycle?

The Software Development Life Cycle (SDLC) illustrates the phases of life a piece of software goes through from the point of its creation. Similarly, the Software Testing Life Cycle (STLC) illustrates the phases of testing that a certain piece of software must go through in order to meet certain specified quality requirements. 

STLC defines steps that should be followed when attempting to thoroughly test a piece of software in a planned manner. Each phase of the software testing life cycle has a purpose, and defines a goal that needs to be achieved in order to further test and ensure the quality of the software.

How is the STLC different from the SDLC?

Although the two life cycles are similar in that they are both generally depicted as having six steps and are centered around a piece of software; Significant differences exist between the STLC and SDLC.  

The main difference between these two life cycles is that the SDLC centers around making a piece of software and dealing with the requirements and responsibilities that come with it. However the STLC centers around testing a piece of software in order to find and fix any defects that may exist. 

What are the Phases of the STLC?

The phases of the STLC can vary depending on the team’s priorities and the software project in question. However the rudimentary phases in every STLC are common for most software projects.

As illustrated above the STLC has 7 major phases which are cycled through clockwise by test engineers.

Detailed Outlines of the STLC Phases

1. Identify and Define Requirements

The first phase of the life cycle directs test engineers to identify the aspects of the application that need to be tested and define the requirements for the tests. This phase also encompasses the definition of what kinds of tests need to be performed.  

During the execution of this phase the QA team will often try to define which tests need to be prioritized and where they should focus their efforts. 

Often the team may identify that they don’t quite understand how or why they are required to test certain aspects of the application. This phase makes the team hash out the details and communicate more effectively with developers and other stakeholders to gain insight as to what exactly is required of them as they test the software.

To summarize, the key steps of this phase are:

• Identifying the different modules of the software that need to be tested.
• Defining what tests need to be performed.
• Defining potential methods for testing, for example: whether or not automation can be utilized for the tests?
• Defining the requirements for these tests,  such as the environment or perhaps other software which may be required.
• Defining the deliverables.

2. Develop a Testing Strategy 

In this phase the planning aspect of the software testing process is carried out. The effort and cost that may be required are estimated in order to create a schedule for the tests. Additionally, the strategy to most efficiently execute tests is sketched out, taking into account the requirements defined in the previous phase.

To summarize, the key steps of this phase are:

• Test Planning, the strategy to efficiently carry out tests is decided,  and a Test Plan document is created.
• The potential budget, time, labor, and effort that may be required, as well as the environment and testing tools are taken into consideration to form a cohesive plan. For example: Whether there is a need to carry out testing on a Real Device Cloud, or another paid testing tool is taken into account in order to devise a plan that fits into the budget available.
• The roles and responsibilities of each member in the team are defined at this phase.

3. Create Test Cases

This phase of the STLC involves fleshing out the actual test cases which will be used to test the software. The test cases are created according to the test plan defined in the previous phase. There may be several iterations of this phase as test engineers design, cross-check, and rework these test cases to adhere to the Test Plan document.

To summarize, the key steps of this phase are:

• Creating and defining test cases.
• Creating test suites if needed.
• Writing automation test cases.
• Generating test data or obtaining test data from other appropriate sources.
• Diligent Test Case Management
• Use Test Case Prioritization

4. Execute Tests

This phase involves setting up the environment required for the test cases and then running the individual test cases. The test scripts written in the previous phase of STLC are executed and the results are logged.

To summarize, the key steps of this phase are:

• Defining the requirements for the test environments which will be needed to execute test cases.
• Setting up the hardware and software environment that will be needed to execute tests.
• Carrying out smoke tests to ensure the environment is suitable.
• Running test cases and test suites.

5. Find, Track and Fix Bugs

This phase involves using the results from the test case execution phase to identify defects and fix them. 

To summarize, the key steps of this phase are:

• Log the test case runs and identify the defects in failed test cases.
• Revert the bugs found to the developer team.
• Create a defect report 
• Retest the fixed versions, and if further defects are found then repeat the previous two steps.

6. Reporting and Analysis

This is the last phase of the Software Testing Life Cycle. This phase constitutes the QA team preparing a final report summarizing the test process and the results obtained. These reports will often compare the expected vs true use of time, cost, and other resources.

To summarize, the key steps of this phase are:

• Create a Test Summary Report and Log Metrics relevant to the test process.
• Preprare a report of the testing process and results.
• Evaluate how accurate the initially defined requirements and strategy were.

To Conclude

STLC is widely utilized in the industry since it aids test engineers in carrying out tests in an organized and well-defined manner. As the engineers systematically cycle through the phases the probability of neglecting some important aspect of the testing process is very low. As the test engineers shift right in the cycle, each phase has been defined to ensure that the engineers are able to accurately identify areas of the software which need testing, create meaningful test cases for those areas, and correct any potential defects. Additionally the progress of the testing cycle is clearly defined leading to easier management and a faster testing process.