## What is Reliability Testing?

Software reliability is the probability that software will work properly in a specified environment and for a given amount of time. * Reliability Testing* is about exercising an application so that failures are discovered and removed before the system is deployed. It is also known as

*and it is a part of*

**Portability Testing***. The purpose of reliability testing is to determine product reliability, and whether the software meets the customer’s reliability requirements.*

**Non-Functional Testing****According to ANSI, Software Reliability is defined as: The probability of failure-free software operation for a specified period of time in a specified environment.**

For *reliability testing*, data is gathered from various stages of development, such as the design and operating stages. Statistical samples are obtained from the software products to test for the reliability of the software. Once sufficient data is gathered, statistical studies are done. Time constraints are handled by applying fixed dates or deadlines for the tests to be performed. The data is gathered carefully so that each data has some purpose and gets its expected precision.

Using the following formula, the probability of failure is calculated by testing a sample of all available input.

**Probability = Number of failing cases / Total number of cases under consideration**

*Objectives of Reliability Testing*

*To find the number of failures occurring in a specified amount of time.**To find the mean life of the software.**To discover the main cause of failure.*