What is Reliability testing?
Reliability Testing is an important software testing technique that is performed by the team to ensure that the software is performing and functioning consistently in each environmental condition as well as in a specified period. It ensures that product is fault free and is reliable for its intended purpose.
Reliability Testing incorporates the results from both functional and non-functional testing such as Stress testing, Security testing, Functional testing, Production testing and more.
This enables the team to determine various problems in software design and functionality.
Categories of Software Reliability
Software reliability is a key part in software quality. The study of software reliability can be categorized into three parts:
Software reliability modeling has matured to the point that meaningful results can be obtained by applying suitable models to the problem.
There are many models exist, but no single model can capture a necessary amount of the software characteristics. Assumptions and abstractions must be made to simplify the problem. There is no single model that is universal to all the situations.
Software reliability measurement is naive. Measurement is far from commonplace in software, as in other engineering field. “How good is the software, quantitatively?” As simple as the question is, there is still no good answer.
Software reliability can not be directly measured, so other related factors are measured to estimate software reliability and compare it among products. Development process, faults and failures found are all factors related to software reliability.
Software reliability improvement is hard. The difficulty of the problem stems from insufficient understanding of software reliability and in general, the characteristics of software. Until now there is no good way to conquer the complexity problem of software.
Complete testing of a moderately complex software module is infeasible. Defect-free software product can not be assured. Realistic constraints of time and budget severely limits the effort put into software reliability improvement.
Approaches to Reliability Testing & Setting of Reliability Test Objectives
If the project context demands different types of reliability testing, the approach to reliability testing is governed by a following three factors:
1) Identified risks, in particular those relating to safety-critical systems
2) Applicable standards
3) Available resources
When planning an approach to reliability tests it is worth bearing in mind that some tests will be defined with one aspect of reliability in focus but which might also be applicable to other reliability aspects. If we decide, for example, to evaluate the recoverability of a system, we may first need to cause that system to fail. The very act of defining these tests (i.e., getting the system to fail) may give us insights into the fault tolerance of our system.
Types Of Reliability Tests
Developers can use these three main types of reliability testing to test certain aspects of the software. This makes sense given the fact that software can be very complex. As such, teams will need to focus on a certain area to understand where any issues lie.
1. Feature Testing
As the client-facing part of the software, this is very important to test. Software failure can lead to not only bad user experience but also problems that could negatively affect a business.
As the name suggests, feature testing tests all of the features of a software product. This is the first step in the reliability testing process.
First, you will test all features once. Then, reduce the interaction between features so that testing teams can check the execution of each feature once again. This ensures that the features work as they should each time.
2. Load Testing
All software features must work correctly. But, it is equally as important to make sure that these features can operate at scale. Especially when developing an enterprise product.
After feature testing, you can then perform load tests. This is to test all features under the maximum workload to see how they function.
Once complete, testing teams can get a good idea of how the software performs under pressure.
3. Regression Testing
Since software development is an ongoing process, developers use regression testing to test the software for bugs. Then they fix any bugs and perform the tests again to ensure no new issues occur.
Factors Influencing Reliability Testing
The process of reliability testing is influenced by few aspects, which impact the output delivered by this testing. Few of these factors are:
- The number of issues and faults present in the system.
- The way users operate the system.
- Number of test executed by the team.