CHAPTER 2 Testing Throughout the Software Life Cycle The University of Lahore A “W4” Category University Lecture 8 CHAPTER 2 Testing Throughout the Software Life Cycle 19/09/2018

The University of Lahore A “W4” Category University Chapter Contents Commonly applied software development models. Test levels Test types How maintenances influences the test process, levels and types How testing can be organized 19/09/2018

The University of Lahore A “W4” Category University 19/09/2018

The University of Lahore A “W4” Category University manifest 19/09/2018

The University of Lahore A “W4” Category University Waterfall Model Waterfall model is a model in which tasks are executed in sequential fashion. We starts at the top of the waterfall with the requirements and flow down through the various tasks finishing with implementation into live environment. 19/09/2018

The University of Lahore A “W4” Category University 19/09/2018

REVIEW The University of Lahore Requirements (What is requirement?) A “W4” Category University REVIEW Requirements (What is requirement?) Carry out the preliminary study of the situation Decide exactly what the problem is? Feasibility Study Cost analysis Decide whether or not to continue with the project? 19/09/2018

The University of Lahore A “W4” Category University Analysis Study the existing system in detail is called analysis. Interview users of the current system Read any manual or instructions which are in use Observe the current system in operation Questionnaires 19/09/2018

The University of Lahore A “W4” Category University Designing Data capture forms Type of user interface Validations methods-how is input data going to be test? Programs-if some new programs has to be written then they have to be designed at this stage Input screens Output screens System flowcharts Program flowcharts 19/09/2018

The University of Lahore A “W4” Category University Construction & Testing Coding (any new program have to be written) System testing. Test data is designed and the results are forecast Acceptance testing. The users of the new system check it user documentation is prepared Technical documentation is prepared users are trained to use the new system 19/09/2018

The University of Lahore A “W4” Category University Implementation - Conversion File conversion Software and hardware installation System conversion System Maintenance and Review Keep watching on the new system Repair faults in both hardware and software Upgrade the system as requirements change 19/09/2018

The University of Lahore A “W4” Category University Problems/Challenges associated with Waterfall Model Testing tends to happen towards the end of the project life cycle, so defects are detected close to the live implementation date. Difficult to carry out numerous alterations for a particular phase. One phase has to be complete before moving onto the next phase. 19/09/2018

The University of Lahore A “W4” Category University Partitioning of the project into different stages makes it difficult to respond to changing customer requirements. Unrealistic to expect accurate requirements so early in the project Therefore, this model is only appropriate when the requirements are well-understood The changes will be limited during the design process. Few business systems have stable requirements. 19/09/2018

The University of Lahore A “W4” Category University Advantages of Waterfall Model Most common Simple to understand and use Easy to manage Phases are processed and completed individually where requirements are well understood 19/09/2018

The University of Lahore A “W4” Category University V - Model The V-model is a model that illustrates how testing activities (verification and validation) can be integrated into each phase of the life cycle. 3 Levels of V-Model Procedure (What has to be done?) Methods (How the tasks are to be performed?) Tool Requirements (What is to be used to carry out the tasks?) 19/09/2018

The University of Lahore A “W4” Category University The V-Model is structured into four functional parts, called submodels. Project Management (PM) tasks The PM submodel states that the staff members should participate in all activities. Plans, controls and informs the SD, QA and CM submodels. Job selection activity 19/09/2018

The University of Lahore A “W4” Category University Software/System Development (SD) Develops the software/system Big emphasis on Commercial Off The Shelf soft wares COTS must be given special attention. Quality Assurance (QA) Access the product or software Compares the product or software with the plans and requirements. It suggest improvements if the product is rejected 19/09/2018

The University of Lahore A “W4” Category University Configuration Management (CM) Administrates the product generated 19/09/2018

The University of Lahore A “W4” Category University V - Model Test Level “A group of test activities that are organized and managed together in V-Model.” Types of Test Levels Component Testing Integration Testing Acceptance Testing System Testing 19/09/2018

The University of Lahore A “W4” Category University Component Testing Searches for defects and verifies the functioning of software components (modules, programs, objects, classes etc) that are separately testable. Integration Testing Tests interfaces between components, interactions to different parts of a system such as OS, file system and hardware. System Testing Concerned with the behaviour of the whole system/product. Acceptance Testing Validation testing with respect to user needs, requirements and expectations. 19/09/2018

Verification & Validation The University of Lahore A “W4” Category University Verification & Validation Verification Have you built the product right? Does the product meet system specification? Validation Have you built the right product? Does the product meet user expectations? It is possible that a software application may fulfill its specification but it may deviate from users expectations or their desired behaviour. That means, software is verified but not validated. 19/09/2018

Verification & Validation The University of Lahore A “W4” Category University Verification & Validation 19/09/2018

Verification & Validation The University of Lahore A “W4” Category University Verification & Validation 19/09/2018

The University of Lahore A “W4” Category University V - Model 19/09/2018

The University of Lahore A “W4” Category University V - Model 19/09/2018

The University of Lahore A “W4” Category University V - Model Represent testing where system is validated Specifications or requirements 19/09/2018

The University of Lahore A “W4” Category University Comparisons Waterfall Vs V-Model Waterfall Model V-Model the start of the next phase will occur at the completion of the previous phase. development and testing processes will occur simultaneously to save the time as well as money. the output of each phase will become input to the next phase. verification we can also do the validations. we can't go back in the waterfall model. We can design the test case for acceptance test when requirement phase is carried out and so on…… If any defect you can identify the risk, time and cost of the s/w is very high. If any defect you can identify risk, cost and time of the s/w is very low. 19/09/2018