What is STLC (Software Testing Life Cycle)

STLC - Software Testing Life Cycle :

There is a systematic cycle to software testing, although it varies from organization to organization

Software Testing Life Cycle:

Software testing life cycle or STLC refers to a comprehensive group of testing related actions specifying details of every action along with the specification of the best time to perform such actions. There can not be a standardized testing process across various organizations, however every organization involved in software development business, defines & follows some sort of testing life cycle.

STLC by & large comprises of following Six Sequential Phases: 

1) Planning of Tests

2) Analysis of Tests

3) Designing of Tests 

4) Creation & Verification of Tests

5) Execution of Testing Cycles

6) Performance Testing, Documentation

7) Actions after Implementation

Every company follows its own software testing life cycle to suit its own requirements, culture & available resources. The software testing life cycle can’t be viewed in isolation, rather it interacts with the every phase of Software Development Life Cycle (SDLC). Prime focus of the software testing life cycle is on managing & controlling all activities of software testing. Testing might be manual testing or an automated testing using some tool.

1) Planning of Tests:

In this phase a senior person like the project manager plans & identifies all the areas where testing efforts need to be applied, while operating within the boundaries of constraints like resources & budget. Unless judicious planning is done in the beginning, the result can be catastrophic with emergence of a poor quality product, dissatisfying the ultimate customer. Planning is not limited just to the initial phase, rather it is a continuous exercise extending till the end. 

During the planning stage, the team of senior level persons comes out with an outline of Testing Plan at High Level. The High Level Test Plan comprehensively describes the following:

• Scope of Testing : Defining the areas to be tested, identification of features to be covered during testing
• Identification of Approaches for Testing: Identification of approaches including types of testing
• Defining Risks: Identification of different types of risks involved with the decided plan
• Identification of resources : Identification of resources like man, materials & machines which need to be deployed during Testing
• Time schedule: For performing the decided testing is aimed to deliver the end product as per the commitment made to the customer. 

Involvement of software testers begins in the planning phase of the software development life cycle. During the design phase, testers work with developers in determining what aspects of a design are testable and with what parameters those tests will work.

2) Analysis of Tests:

Based upon the High Level Test Plan Document, further nitty-gritty’s covering the following are worked out.

• Identification of Types of Testing to be performed during various stages of Software Development Life Cycle.
• Identification of extent to which automation needs to be done.
• Identification of the time at which automation is to be carried out.
• Identification of documentation required for automated testing

The Software project can’t be successful unless there is frequent interaction among various teams involved in Coding & Testing with the active involvement of the Project Managers, Business Analysts or even the customer. Any deficiencies in the decided test plans come to the surface, during such meetings of cross-functional teams. This provides an opportunity to have a rethinking & refining the strategies decided for testing.

Based upon the customer requirements a detailed matrix for functional validation is prepared to cover the following areas:

• Ensure that each & every business requirement is getting covered through some test case or the other.
• Identification of the test cases best suited to the automated testing
• Identification of the areas to covered for performance testing and stress testing
• Carry out detailed review of documentation covering areas like Customer Requirements, Product Features & Specifications and Functional Design etc.

3) Designing of Tests:

This phase involves the following:

• Further polishing of various Test Cases, Test Plans
• Revision & finalization of Matrix for Functional Validation.
• Finalization of risk assessment methodologies.
• In case line of automation is to be adopted, identification of test cases suitable for automation.
• Creation of scripts for Test cases decided for automation.
• Preparation of test data.
• Establishing Unit testing Standards including defining acceptance criteria
• Revision & finalization of testing environment.

4) Construction and verification:

This phase involves the following:

• Finalization of test plans and test cases
• Completion of script creation for test cased decided for automation.
• Completion of test plans for Performance testing & Stress testing.
• Providing technical support to the code developers in their effort directed towards unit testing.
• Bug logging in bug repository & preparation of detailed bug report.
• Performing Integration testing followed by reporting of defects detected if any.

5) Execution of Testing Cycles:

This phase involves the following:

• Completion of test cycles by executing all the test cases till a predefined stage reaches or a stage of no detection of any more errors reach.
• This is an iterative process involving execution of Test Cases, Detection of Bugs, Bug Reporting, Modification of test cases if felt necessary, Fixing of bugs by the developers & finally repeating the testing cycles.

6) Performance Testing, Documentation & Actions after Implementation:

This phase involves the following:

• Execution of test cases pertaining to performance testing & stress testing.
• Revision & finalization of test documentation
• Performing Acceptance testing, load testing followed by recovery testing
• Verification of the software application by simulating conditions of actual usage.

7) Actions after Implementation:

This phase involves the following:

• Evaluation of the entire process of testing.
• Documentation of TGR (Things Gone Right) & TGW (Things Gone Wrong) reports. Identification of approaches to be followed in the event of occurrence of similar defects & problems in the future.
• Creation of comprehensive plans with a view to refine the process of Testing.
• Identification & fixing of newly cropped up errors on continuous basis.

Winding up of the test environment & restoration of all test equipment to the original base line conditions.