testing

[padmajasrinath]

can anyone tell me about v-model?

[qtptester]

Types of Testing

The level of test is the primary focus of a system and derives from the way a software system is designed and built up. Conventionally this is known as the "V" model, which maps the types of test to each stage of development.

for graphical reprasentation I'm adding an attachment...

Component Testing

Starting from the bottom the first test level is "Component Testing", sometimes called Unit Testing. It involves checking that each feature specified in the "Component Design" has been implemented in the component.

In theory an independent tester should do this, but in practise the developer usually does it, as they are the only people who understand how a component works. The problem with a component is that it performs only a small part of the functionality of a system, and it relies on co-operating with other parts of the system, which may not have been built yet. To overcome this, the developer either builds, or uses special software to trick the component into believing it is working in a fully functional system.
Interface Testing

As the components are constructed and tested they are then linked together to check if they work with each other. It is a fact that two components that have passed all their tests, when connected to each other produce one new component full of faults. These tests can be done by specialists, or by the developers.

Interface Testing is not focussed on what the components are doing but on how they communicate with each other, as specified in the "System Design". The "System Design" defines relationships between components, and this involves stating:

* What a component can expect from another component in terms of services.
* How these services will be asked for.
* How they will be given.
* How to handle non-standard conditions, i.e. errors.

Tests are constructed to deal with each of these.

The tests are organised to check all the interfaces, until all the components have been built and interfaced to each other producing the whole system.
System Testing

Once the entire system has been built then it has to be tested against the "System Specification" to check if it delivers the features required. It is still developer focussed, although specialist developers known as systems testers are normally employed to do it.

In essence System Testing is not about checking the individual parts of the design, but about checking the system as a whole. In effect it is one giant component.

System testing can involve a number of specialist types of test to see if all the functional and non-functional requirements have been met. In addition to functional requirements these may include the following types of testing for the non-functional requirements:

* Performance - Are the performance criteria met?
* Volume - Can large volumes of information be handled?
* Stress - Can peak volumes of information be handled?
* Documentation - Is the documentation usable for the system?
* Robustness - Does the system remain stable under adverse circumstances?

There are many others, the needs for which are dictated by how the system is supposed to perform.
Acceptance Testing

Acceptance Testing checks the system against the "Requirements". It is similar to systems testing in that the whole system is checked but the important difference is the change in focus:

* Systems Testing checks that the system that was specified has been delivered.
* Acceptance Testing checks that the system delivers what was requested.

The customer, and not the developer should always do acceptance testing. The customer knows what is required from the system to achieve value in the business and is the only person qualified to make that judgement. To help them courses and training are available.

The forms of the tests may follow those in system testing, but at all times they are informed by the business needs.
Release Testing

Even if a system meets all its requirements, there is still a case to be answered that it will benefit the business. The linking of "Business Case" to Release Testing is looser than the others, but is still important.

Release Testing is about seeing if the new or changed system will work in the existing business environment. Mainly this means the technical environment, and checks concerns such as:

* Does it affect any other systems running on the hardware?
* Is it compatible with other systems?
* Does it have acceptable performance under load?

These tests are usually run the by the computer operations team in a business. The answers to their questions could have significant a financial impact if new computer hardware should be required, and adversely affect the "Business Case".

It would appear obvious that the operations team should be involved right from the start of a project to give their opinion of the impact a new system may have. They could then make sure the "Business Case" is relatively sound, at least from the capital expenditure, and ongoing running costs aspects. However in practise many operations teams only find out about a project just weeks before it is supposed to go live, which can result in major problems.
Regression Tests

With modern systems one person's system, becomes somebody else's component. It follows that all the above types of testing could be repeated at many levels in order to deliver the final value to the business. In fact every time a system is altered.

[pavanhyd]

look at Software Testing - Testing Tutorials, Testing Tools, Testing Softwares, Testing Jobs, Testing Techniques

[caradoc]

The V-Model defines a uniform procedure for IT product development.The V-model was developed to regulate the software development process within the German federal administration. It describes the activities and results that have to be produced during software development.The V-model is a graphical representation of the system development lifecycle. It summarizes the main steps to be taken in conjunction with the corresponding deliverables within computerized system validation framework.

[sudhareddyl]

hi , can any one pls tell me about testing methodologies? can u pls send it to my mail id : sudha.reddy@lycos.com.. thanks

[kkrddy]

Originally Posted by padmajasrinath

can anyone tell me about v-model?

'V' shape model describes about the process about the construting the application at a time all the Analysing, designing, coding and testing will be done at a time. i.e once coding finishes it'll go to tester to test for bugs if we got OK form tester we can immediately start coding after coding again send to tester he'll check for BUGS and will send back to programmer then he,programmer can finish up by implementing the project.
it is the model what is using by most of the companies.


v model is model in which testing is done prallelly with development.left side of v model ,reflect development input for the corresponding testing activities.

V Model is the process model to provide quality product by combining SDLC and STLC. In this model Both SDLC & STLC works parallely. Left Hand side of the V model contains SDLC in downhill direction whereas right hand side of the V model contains STLC in Uphill direction


V model is the classic software development model. It encapsulates the steps in Verification and Validation phases for each step in the SDLC. For each phase, the subsequent phase becomes the verification (QA) phase and the corresponding testing phase in the other arm of the V becomes the validating (Testing) phase

Traditional Water fall model will not allow to do the testing and the coding process in parallel. V - model in the SDLC will allow the process to have testing and coding as a parallel activity which enables the changes to occur more dynamic.


V- model is a process where the development and testing phases can do parallely. For every development phase there is a testing phase. Development phases are called as verification whereas testing phases are called as validation. Here verification means the software implements correctly or not. Validation means the software that has been built is traceable to the customer requirements or not.

[kkrddy]

Originally Posted by padmajasrinath

can anyone tell me about v-model?

The V-model was originally developed from the waterfall software process model.
The four main process phases – requirements, specification, design and implementation – have a corresponding verification and validation testing phase. Implementation of modules is tested by unit testing, system design is tested by integration testing, system specifications are tested by system testing and finally acceptance testing verifies the requirements. The V-model gets its name from the timing of the phases. Starting from the requirements, the system is developed one phase at a time until the lowest phase, the implementation phase, is finished. At this stage testing begins, starting from unit testing and moving up one test level at a time until the acceptance testing phase is completed.
[1] The V-model is easy to understand, but the timing of the phases where testing occurs after all implementation is done, is not an adequate approach in today’s iterative software processes. However, the test levels from the V-model which associate a certain process phase with a testing phase is still relevant and will be used in this project. When the test levels from the V-model are used in parallel with development, and more importantly, when the different levels are tested simultaneously in multiple
iterations, the V-model testing method can become an effective and manageable testing process.