by Dinesh Thakur Category: Software Engineering

The formal methods model is concerned with the application of a mathematical technique to design and implement the software. This model lays the foundation for developing a complex system and supporting the program development. The formal methods used during the development process provide a mechanism for eliminating problems, which are difficult to overcome using other software process models. The software engineer creates formal specifications for this model. These methods minimize specification errors and this result in fewer errors when the user begins using the system.

by Dinesh Thakur Category: Software Engineering

On successful culmination of software testing, debugging is performed. Debugging is defined as a process of analyzing and removing the error. It is considered necessary in most of the newly developed software or hardware and in commercial products/ personal application programs. For complex products, debugging is done at all the levels of the testing.

by Dinesh Thakur Category: Software Engineering

In the build and fix model (also referred to as an ad hoc model), the software is developed without any specification or design. An initial product is built, which is then repeatedly modified until it (software) satisfies the user. That is, the software is developed and delivered to the user. The user checks whether the desired functions 'are present. If not, then the software is changed according to the needs by adding, modifying or deleting functions. This process goes on until the user feels that the software can be used productively. However, the lack of design requirements and repeated modifications result in loss of acceptability of software. Thus, software engineers are strongly discouraged from using this development approach.

by Dinesh Thakur Category: Software Engineering

Any cost estimation model can be viewed as a function that outputs the cost estimate. The basic idea of having a model or procedure for cost estimation is that it reduces the problem of estimation of determining the value of he “key parameters” that characterize the project, based on which the cost can be estimated.

by Dinesh Thakur Category: Software Engineering

To perform testing in a planned and systematic manner, software testing strategy is developed. A testing strategy is used to identify the levels of testing which are to be applied along with the methods, techniques, and tools to be used during testing. This strategy also decides test cases, test specifications, test case decisions, and puts them together for execution.

Developing a test strategy, which efficiently meets the requirements of an organization, is critical to the success of software development in that organization. Therefore, a software testing strategy should contain complete information about the procedure to perform testing and the purpose and requirements of testing.

The choice of software testing strategy is highly dependent on the nature of the developed software. For example, if the software is highly data intensive then a strategy that checks structures and values properly to ensure that all inputs given to the software are correct and complete should be developed. Similarly, if it is transaction intensive then the strategy should be such that it is able to check the flow of all the transactions. The design and architecture of the software are also useful in choosing testing strategy. A number of software testing strategies are developed in the testing process. All these strategies provide the tester a template, which is used for testing. Generally, all testing strategies have following characteristics.

  1. Testing proceeds in an outward manner. It starts from testing the individual units, progresses to integrating these units, and finally, moves to system testing.
  2. Testing techniques used during different phases of software development are different.
  3. Testing is conducted by the software developer and by an ITG.
  4. Testing and debugging should not be used synonymously. However, any testing strategy must accommodate debugging with itself.

Types of Software Testing Strategies

There are different types of software testing strategies, which are selected by the testers depending upon the nature and size of the software. The commonly used software testing strategies are listed below.

                     Types of Software Testing Strategy

  1. Analytic testing strategy: This uses formal and informal techniques to access and prioritize risks that arise during software testing. It takes a complete overview of requirements, design, and implementation of objects to determine the motive of testing. In addition, it gathers complete information about the software, targets to be achieved, and the data required for testing the software.
  2. Model-based testing strategy: This strategy tests the functionality of the software according to the real world scenario (like software functioning in an organization). It recognizes the domain of data and selects suitable test cases according to the probability of errors in that domain.
  3. Methodical testing strategy: It tests the functions and status of software according to the checklist, which is based on user requirements. This strategy is also used to test the functionality, reliability, usability, and performance of the software.
  4. Process-oriented testing strategy: It tests the software according to already existing standards such as the IEEE standards. In addition, it checks the functionality of the software by using automated testing tools.
  5. Dynamic testing strategy: This tests the software after having a collective decision of the testing team. Along with testing, this strategy provides information about the software such as test cases used for testing the errors present in it.
  6. Philosophical testing strategy: It tests the software assuming that any component of the software can stop functioning anytime. It takes help from software developers, users and systems analysts to test the software.

A testing strategy should be developed with the intent to provide the most effective and efficient way of testing the software. While developing a testing strategy, some questions arise such as: when and what type of testing is to be done? What are the objectives of testing? Who is responsible for performing testing? What outputs are produced as a result of testing? The inputs that should be available while developing a testing strategy are listed below.

  1. Type of development project
  2. Complete information about the hardware and software components that are required to develop the software
  3. Risks involved
  4. Description of the resources that are required for testing
  5. Description of all testing methods that are required to test various phases of SDLC
  6. Details of all the attributes that the software is unable to provide. For example, software cannot describe its own limitations.

The output produced by the software testing strategy includes a detailed document, which indicates the entire test plan including all test cases used during the testing phase. A testing strategy also specifies a list of testing issues that need to be resolved.

An efficient software testing strategy includes two types of tests, namely, low-level tests and high-level tests. Low-level tests ensure correct implementation of small part of the source code and high-level tests ensure that major software functions are validated according to user requirements. A testing strategy sets certain milestones for the software such as final date for completion of testing and the date of delivering the software. These milestones are important when there is limited time to meet the deadline.

In spite of these advantages, there are certain issues that need to be addressed for successful implementation of software testing strategy. These issues are discussed here.

  1. In addition to detecting errors, a good testing strategy should also assess portability and usability of the software.
  2. It should use quantifiable manner to specify software requirements such as outputs expected from software, test effectiveness, and mean time to failure which should be clearly stated in the test plan.
  3. It should improve testing method continuously to make it more effective.
  4. Test plans that support rapid cycle testing should be developed. The feedback from rapid cycle testing can be used to control the corresponding strategies.
  5. It should develop robust software, which is able to test itself using debugging techniques.
  6. It should conduct formal technical reviews to evaluate the test cases and test strategy. The formal technical reviews can detect errors and inconsistencies present in the testing process.

by Dinesh Thakur Category: Software Engineering

The first level of testing is called unit testing. In this, different modules are tested against the specifications produced during design for the modules. Unit testing is essentially for verification of the code produced during the coding phase, and hence the goal is to test the internal logic of the modules. It is typically done by the programmer of the module.

by Dinesh Thakur Category: Software Engineering

In functional testing the structure of the program is not considered. Test cases are decided solely on the basis of requirements or specifications of the program or module, and the internals of the module or the program are not considered for selection of test cases.

by Dinesh Thakur Category: Software Engineering

The incremental model (also known as iterative enhancement model) comprises the features of waterfall model in an iterative manner. The waterfall model performs each phase for developing complete software whereas the incremental model has phases similar to the linear sequential model arid has an iterative nature of prototyping. During the implementation phase, the project is divided into small subsets known as increments that are implemented individually. This model comprises several phases where each phase produces an increment. These increments are identified in the beginning of the development process and the entire process from requirements gathering to delivery of the product is carried out for each increment.

by Dinesh Thakur Category: Software Engineering

A development process consists of various phases, each phase ending with a defined output. The phases are performed in an order specified by the process model being followed. The main reason for having a phased process is that it breaks the problem of developing software into successfully performing a set of phase, each handling a different concern of software development.

by Dinesh Thakur Category: Software Engineering

In general, testing commences with a test plan and terminates with acceptance testing. A test plan is a general document for the entire project that defines the scope, approach to be taken, and the schedule of testing as well as identifies the test items for the entire testing process and the person responsible for the different activities of testing.

About Dinesh Thakur

Dinesh ThakurDinesh Thakur holds an B.SC (Computer Science), MCSE, MCDBA, CCNA, CCNP, A+, SCJP certifications. Dinesh authors the hugely popular blog. Where he writes how-to guides around Computer fundamental , computer software, Computer programming, and web apps. For any type of query or something that you think is missing, please feel free to Contact us.

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